231091657 has 2 divisors, whose sum is σ = 231091658. Its totient is φ = 231091656.

The previous prime is 231091579. The next prime is 231091687. The reversal of 231091657 is 756190132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139334416 + 91757241 = 11804^2 + 9579^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231091657 is a prime.

It is not a weakly prime, because it can be changed into another prime (231091687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115545828 + 115545829.

It is an arithmetic number, because the mean of its divisors is an integer number (115545829).

Almost surely, 2^231091657 is an apocalyptic number.

It is an amenable number.

231091657 is a deficient number, since it is larger than the sum of its proper divisors (1).

231091657 is an equidigital number, since it uses as much as digits as its factorization.

231091657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 231091657 is about 15201.6991484505. The cubic root of 231091657 is about 613.6603859520.

The spelling of 231091657 in words is "two hundred thirty-one million, ninety-one thousand, six hundred fifty-seven".