642699931057 has 2 divisors, whose sum is σ = 642699931058. Its totient is φ = 642699931056.

The previous prime is 642699931051. The next prime is 642699931061. The reversal of 642699931057 is 750139996246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 507728927601 + 134971003456 = 712551^2 + 367384^2 .

It is a cyclic number.

It is not a de Polignac number, because 642699931057 - 2³⁹ = 92944117169 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 642699930986 and 642699931004.

It is not a weakly prime, because it can be changed into another prime (642699931051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321349965528 + 321349965529.

It is an arithmetic number, because the mean of its divisors is an integer number (321349965529).

Almost surely, 2^642699931057 is an apocalyptic number.

It is an amenable number.

642699931057 is a deficient number, since it is larger than the sum of its proper divisors (1).

642699931057 is an equidigital number, since it uses as much as digits as its factorization.

642699931057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22044960, while the sum is 61.

The spelling of 642699931057 in words is "six hundred forty-two billion, six hundred ninety-nine million, nine hundred thirty-one thousand, fifty-seven".