31719500257 has 2 divisors, whose sum is σ = 31719500258. Its totient is φ = 31719500256.

The previous prime is 31719500249. The next prime is 31719500311. The reversal of 31719500257 is 75200591713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16410634816 + 15308865441 = 128104^2 + 123729^2 .

It is a cyclic number.

It is not a de Polignac number, because 31719500257 - 2³ = 31719500249 is a prime.

It is a super-2 number, since 2×31719500257² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31719500207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15859750128 + 15859750129.

It is an arithmetic number, because the mean of its divisors is an integer number (15859750129).

Almost surely, 2^31719500257 is an apocalyptic number.

It is an amenable number.

31719500257 is a deficient number, since it is larger than the sum of its proper divisors (1).

31719500257 is an equidigital number, since it uses as much as digits as its factorization.

31719500257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 66150, while the sum is 40.

The spelling of 31719500257 in words is "thirty-one billion, seven hundred nineteen million, five hundred thousand, two hundred fifty-seven".