31699649 has 2 divisors, whose sum is σ = 31699650. Its totient is φ = 31699648.

The previous prime is 31699637. The next prime is 31699651. The reversal of 31699649 is 94699613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22657600 + 9042049 = 4760^2 + 3007^2 .

It is a cyclic number.

It is not a de Polignac number, because 31699649 - 2²⁰ = 30651073 is a prime.

It is a Sophie Germain prime.

Together with 31699651, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (31699669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15849824 + 15849825.

It is an arithmetic number, because the mean of its divisors is an integer number (15849825).

Almost surely, 2^31699649 is an apocalyptic number.

It is an amenable number.

31699649 is a deficient number, since it is larger than the sum of its proper divisors (1).

31699649 is an equidigital number, since it uses as much as digits as its factorization.

31699649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 314928, while the sum is 47.

The square root of 31699649 is about 5630.2441332504. The cubic root of 31699649 is about 316.4837999906.

The spelling of 31699649 in words is "thirty-one million, six hundred ninety-nine thousand, six hundred forty-nine".