31696909 has 2 divisors, whose sum is σ = 31696910. Its totient is φ = 31696908.

The previous prime is 31696879. The next prime is 31696927. The reversal of 31696909 is 90969613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31696900 + 9 = 5630^2 + 3^2 .

It is a cyclic number.

It is not a de Polignac number, because 31696909 - 2²³ = 23308301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31696939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15848454 + 15848455.

It is an arithmetic number, because the mean of its divisors is an integer number (15848455).

Almost surely, 2^31696909 is an apocalyptic number.

It is an amenable number.

31696909 is a deficient number, since it is larger than the sum of its proper divisors (1).

31696909 is an equidigital number, since it uses as much as digits as its factorization.

31696909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 78732, while the sum is 43.

The square root of 31696909 is about 5630.0007992895. Note that the first 3 decimals coincide. The cubic root of 31696909 is about 316.4746811662.

The spelling of 31696909 in words is "thirty-one million, six hundred ninety-six thousand, nine hundred nine".