31718689 has 2 divisors, whose sum is σ = 31718690. Its totient is φ = 31718688.

The previous prime is 31718681. The next prime is 31718693. The reversal of 31718689 is 98681713.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30338064 + 1380625 = 5508^2 + 1175^2 .

It is a cyclic number.

It is not a de Polignac number, because 31718689 - 2³ = 31718681 is a prime.

It is not a weakly prime, because it can be changed into another prime (31718681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15859344 + 15859345.

It is an arithmetic number, because the mean of its divisors is an integer number (15859345).

Almost surely, 2^31718689 is an apocalyptic number.

It is an amenable number.

31718689 is a deficient number, since it is larger than the sum of its proper divisors (1).

31718689 is an equidigital number, since it uses as much as digits as its factorization.

31718689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 31718689 is about 5631.9347474913. The cubic root of 31718689 is about 316.5471513282.

The spelling of 31718689 in words is "thirty-one million, seven hundred eighteen thousand, six hundred eighty-nine".