165508631 has 2 divisors, whose sum is σ = 165508632. Its totient is φ = 165508630.

The previous prime is 165508627. The next prime is 165508633. The reversal of 165508631 is 136805561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165508631 - 2² = 165508627 is a prime.

It is a super-2 number, since 2×165508631² = 54786213870988322, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 165508633, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 165508591 and 165508600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165508633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82754315 + 82754316.

It is an arithmetic number, because the mean of its divisors is an integer number (82754316).

Almost surely, 2^165508631 is an apocalyptic number.

165508631 is a deficient number, since it is larger than the sum of its proper divisors (1).

165508631 is an equidigital number, since it uses as much as digits as its factorization.

165508631 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 165508631 is about 12865.0157792363. The cubic root of 165508631 is about 549.0436615010.

The spelling of 165508631 in words is "one hundred sixty-five million, five hundred eight thousand, six hundred thirty-one".