31916897 has 2 divisors, whose sum is σ = 31916898. Its totient is φ = 31916896.

The previous prime is 31916861. The next prime is 31916947. The reversal of 31916897 is 79861913.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29495761 + 2421136 = 5431^2 + 1556^2 .

It is an emirp because it is prime and its reverse (79861913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31916897 - 2²² = 27722593 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31910897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15958448 + 15958449.

It is an arithmetic number, because the mean of its divisors is an integer number (15958449).

Almost surely, 2^31916897 is an apocalyptic number.

It is an amenable number.

31916897 is a deficient number, since it is larger than the sum of its proper divisors (1).

31916897 is an equidigital number, since it uses as much as digits as its factorization.

31916897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 44.

The square root of 31916897 is about 5649.5041375328. The cubic root of 31916897 is about 317.2051434142.

The spelling of 31916897 in words is "thirty-one million, nine hundred sixteen thousand, eight hundred ninety-seven".