31313021057 has 2 divisors, whose sum is σ = 31313021058. Its totient is φ = 31313021056.

The previous prime is 31313020997. The next prime is 31313021119. The reversal of 31313021057 is 75012031313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23446040641 + 7866980416 = 153121^2 + 88696^2 .

It is a cyclic number.

It is not a de Polignac number, because 31313021057 - 2¹⁰ = 31313020033 is a prime.

It is a super-2 number, since 2×31313021057² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31313021557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656510528 + 15656510529.

It is an arithmetic number, because the mean of its divisors is an integer number (15656510529).

Almost surely, 2^31313021057 is an apocalyptic number.

It is an amenable number.

31313021057 is a deficient number, since it is larger than the sum of its proper divisors (1).

31313021057 is an equidigital number, since it uses as much as digits as its factorization.

31313021057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1890, while the sum is 26.

The spelling of 31313021057 in words is "thirty-one billion, three hundred thirteen million, twenty-one thousand, fifty-seven".