165725531 has 2 divisors, whose sum is σ = 165725532. Its totient is φ = 165725530.

The previous prime is 165725509. The next prime is 165725533. The reversal of 165725531 is 135527561.

165725531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165725531 - 2¹⁸ = 165463387 is a prime.

It is a super-2 number, since 2×165725531² = 54929903250463922, which contains 22 as substring.

Together with 165725533, 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 = 165725491 and 165725500.

It is not a weakly prime, because it can be changed into another prime (165725533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82862765 + 82862766.

It is an arithmetic number, because the mean of its divisors is an integer number (82862766).

Almost surely, 2^165725531 is an apocalyptic number.

165725531 is a deficient number, since it is larger than the sum of its proper divisors (1).

165725531 is an equidigital number, since it uses as much as digits as its factorization.

165725531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31500, while the sum is 35.

The square root of 165725531 is about 12873.4428572935. The cubic root of 165725531 is about 549.2833984172.

The spelling of 165725531 in words is "one hundred sixty-five million, seven hundred twenty-five thousand, five hundred thirty-one".