231499561 has 2 divisors, whose sum is σ = 231499562. Its totient is φ = 231499560.

The previous prime is 231499549. The next prime is 231499579. The reversal of 231499561 is 165994132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 140659600 + 90839961 = 11860^2 + 9531^2 .

It is a cyclic number.

It is not a de Polignac number, because 231499561 - 2⁹ = 231499049 is a prime.

It is not a weakly prime, because it can be changed into another prime (231494561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115749780 + 115749781.

It is an arithmetic number, because the mean of its divisors is an integer number (115749781).

Almost surely, 2^231499561 is an apocalyptic number.

It is an amenable number.

231499561 is a deficient number, since it is larger than the sum of its proper divisors (1).

231499561 is an equidigital number, since it uses as much as digits as its factorization.

231499561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58320, while the sum is 40.

The square root of 231499561 is about 15215.1096282610. The cubic root of 231499561 is about 614.0212346810.

The spelling of 231499561 in words is "two hundred thirty-one million, four hundred ninety-nine thousand, five hundred sixty-one".