231989057 has 2 divisors, whose sum is σ = 231989058. Its totient is φ = 231989056.

The previous prime is 231989053. The next prime is 231989059. The reversal of 231989057 is 750989132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121969936 + 110019121 = 11044^2 + 10489^2 .

It is a cyclic number.

It is not a de Polignac number, because 231989057 - 2² = 231989053 is a prime.

Together with 231989059, 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 = 231988999 and 231989017.

It is not a weakly prime, because it can be changed into another prime (231989053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115994528 + 115994529.

It is an arithmetic number, because the mean of its divisors is an integer number (115994529).

Almost surely, 2^231989057 is an apocalyptic number.

It is an amenable number.

231989057 is a deficient number, since it is larger than the sum of its proper divisors (1).

231989057 is an equidigital number, since it uses as much as digits as its factorization.

231989057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 136080, while the sum is 44.

The square root of 231989057 is about 15231.1869859181. The cubic root of 231989057 is about 614.4537039614.

The spelling of 231989057 in words is "two hundred thirty-one million, nine hundred eighty-nine thousand, fifty-seven".