31909057 has 2 divisors, whose sum is σ = 31909058. Its totient is φ = 31909056.

The previous prime is 31908991. The next prime is 31909067. The reversal of 31909057 is 75090913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29116816 + 2792241 = 5396^2 + 1671^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31909057 is a prime.

It is not a weakly prime, because it can be changed into another prime (31909067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15954528 + 15954529.

It is an arithmetic number, because the mean of its divisors is an integer number (15954529).

Almost surely, 2^31909057 is an apocalyptic number.

It is an amenable number.

31909057 is a deficient number, since it is larger than the sum of its proper divisors (1).

31909057 is an equidigital number, since it uses as much as digits as its factorization.

31909057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8505, while the sum is 34.

The square root of 31909057 is about 5648.8102287119. The cubic root of 31909057 is about 317.1791687507.

The spelling of 31909057 in words is "thirty-one million, nine hundred nine thousand, fifty-seven".