31917598897 has 2 divisors, whose sum is σ = 31917598898. Its totient is φ = 31917598896.

The previous prime is 31917598879. The next prime is 31917598907. The reversal of 31917598897 is 79889571913.

Together with previous prime (31917598879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26763651216 + 5153947681 = 163596^2 + 71791^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31917598897 is a prime.

It is not a weakly prime, because it can be changed into another prime (31917598597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15958799448 + 15958799449.

It is an arithmetic number, because the mean of its divisors is an integer number (15958799449).

Almost surely, 2^31917598897 is an apocalyptic number.

It is an amenable number.

31917598897 is a deficient number, since it is larger than the sum of its proper divisors (1).

31917598897 is an equidigital number, since it uses as much as digits as its factorization.

31917598897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34292160, while the sum is 67.

The spelling of 31917598897 in words is "thirty-one billion, nine hundred seventeen million, five hundred ninety-eight thousand, eight hundred ninety-seven".