23557531 has 2 divisors, whose sum is σ = 23557532. Its totient is φ = 23557530.

The previous prime is 23557519. The next prime is 23557537. The reversal of 23557531 is 13575532.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 23557531 - 2⁷ = 23557403 is a prime.

It is a super-2 number, since 2×23557531² = 1109914533631922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 23557493 and 23557502.

It is not a weakly prime, because it can be changed into another prime (23557537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11778765 + 11778766.

It is an arithmetic number, because the mean of its divisors is an integer number (11778766).

Almost surely, 2^23557531 is an apocalyptic number.

23557531 is a deficient number, since it is larger than the sum of its proper divisors (1).

23557531 is an equidigital number, since it uses as much as digits as its factorization.

23557531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15750, while the sum is 31.

The square root of 23557531 is about 4853.6100997093. The cubic root of 23557531 is about 286.6662666000. Note that the first 3 decimals are identical.

The spelling of 23557531 in words is "twenty-three million, five hundred fifty-seven thousand, five hundred thirty-one".