165631651 has 2 divisors, whose sum is σ = 165631652. Its totient is φ = 165631650.

The previous prime is 165631633. The next prime is 165631679. The reversal of 165631651 is 156136561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165631651 - 2⁷ = 165631523 is a prime.

It is not a weakly prime, because it can be changed into another prime (165631601) 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, 82815825 + 82815826.

It is an arithmetic number, because the mean of its divisors is an integer number (82815826).

Almost surely, 2^165631651 is an apocalyptic number.

165631651 is a deficient number, since it is larger than the sum of its proper divisors (1).

165631651 is an equidigital number, since it uses as much as digits as its factorization.

165631651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16200, while the sum is 34.

The square root of 165631651 is about 12869.7960745305. The cubic root of 165631651 is about 549.1796596926.

The spelling of 165631651 in words is "one hundred sixty-five million, six hundred thirty-one thousand, six hundred fifty-one".