165136631531 has 2 divisors, whose sum is σ = 165136631532. Its totient is φ = 165136631530.

The previous prime is 165136631477. The next prime is 165136631533. The reversal of 165136631531 is 135136631561.

It is a strong prime.

It is an emirp because it is prime and its reverse (135136631561) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165136631531 is a prime.

It is a super-2 number, since 2×165136631531² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 165136631533, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (165136631533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82568315765 + 82568315766.

It is an arithmetic number, because the mean of its divisors is an integer number (82568315766).

Almost surely, 2^165136631531 is an apocalyptic number.

165136631531 is a deficient number, since it is larger than the sum of its proper divisors (1).

165136631531 is an equidigital number, since it uses as much as digits as its factorization.

165136631531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 41.

The spelling of 165136631531 in words is "one hundred sixty-five billion, one hundred thirty-six million, six hundred thirty-one thousand, five hundred thirty-one".