31649899 has 2 divisors, whose sum is σ = 31649900. Its totient is φ = 31649898.

The previous prime is 31649897. The next prime is 31649921. The reversal of 31649899 is 99894613.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31649899 - 2¹ = 31649897 is a prime.

It is a super-2 number, since 2×31649899² = 2003432213420402, which contains 22 as substring.

Together with 31649897, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31649897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15824949 + 15824950.

It is an arithmetic number, because the mean of its divisors is an integer number (15824950).

Almost surely, 2^31649899 is an apocalyptic number.

31649899 is a deficient number, since it is larger than the sum of its proper divisors (1).

31649899 is an equidigital number, since it uses as much as digits as its factorization.

31649899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 419904, while the sum is 49.

The square root of 31649899 is about 5625.8242951589. The cubic root of 31649899 is about 316.3181481763.

The spelling of 31649899 in words is "thirty-one million, six hundred forty-nine thousand, eight hundred ninety-nine".