31331897 has 2 divisors, whose sum is σ = 31331898. Its totient is φ = 31331896.

The previous prime is 31331887. The next prime is 31331921. The reversal of 31331897 is 79813313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29203216 + 2128681 = 5404^2 + 1459^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31331897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31331837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15665948 + 15665949.

It is an arithmetic number, because the mean of its divisors is an integer number (15665949).

Almost surely, 2^31331897 is an apocalyptic number.

It is an amenable number.

31331897 is a deficient number, since it is larger than the sum of its proper divisors (1).

31331897 is an equidigital number, since it uses as much as digits as its factorization.

31331897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 35.

The square root of 31331897 is about 5597.4902411706. The cubic root of 31331897 is about 315.2551791329.

The spelling of 31331897 in words is "thirty-one million, three hundred thirty-one thousand, eight hundred ninety-seven".