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Properties of the Number 87991

Eighty-Seven Thousand Nine Hundred Ninety-One

Basics

Value: 87990 → 87991 → 87992

Parity: odd

Prime: Yes

Previous Prime: 87977

Next Prime: 88001

Digit Sum: 34

Digital Root: 7

Palindrome: No

Factorization: 87991

Divisors: 1, 87991

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10101011110110111

Octal: 253667

Duodecimal: 42B07

Hexadecimal: 157b7

Square: 7742416081

Square Root: 296.6327695990448

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Primes p such that A001177(p) = (p-1)/7. A308800
Primes of form 210·p + 1 where p is a prime. A51648
Primes of the form triangular(p) + 1, where p is a prime. A231988
Compound filter: a(n) = P(A055881(n), A278236(n)), where P(n,k) is sequence A000027 used as a pairing function. A286381
Compound filter: a(n) = P(A257993(n), A278226(n)), where P(n,k) is sequence A000027 used as a pairing function. A286382
Number of (n+1)X3 0..1 arrays with rows and columns of permanents of all 2X2 subblocks lexicographically nondecreasing, and all 2X2 permanents nonzero. A204734
First of four consecutive primes p,q,r,s such that the sum of numerator and denominator of p/q + q/r, p/q + r/s, and q/r + r/s, are all prime. A355696
Number of walks within N3 (the first octant of Z3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (-1, 1, 1), (1, 0, -1), (1, 1, 1)}. A149647
Integers n such that the century defined by the interval [100n+1, 100n+100] (i.e., the (n+1)-st century) contains exactly one Ormiston prime pair and no other primes. A162895
Squared length of sum of elambda elambda', where elambda is an elementary symmetric function and λ ranges over all partitions of n and λ' is the adjoint (or transpose) of λ. A332302