31649906 has 4 divisors (see below), whose sum is σ = 47474862. Its totient is φ = 15824952.

The previous prime is 31649899. The next prime is 31649921. The reversal of 31649906 is 60994613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60994613 = 59 ⋅1033807.

It can be written as a sum of positive squares in only one way, i.e., 31259281 + 390625 = 5591^2 + 625^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 31649906.

It is an unprimeable number.

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, 7912475 + ... + 7912478.

Almost surely, 2^31649906 is an apocalyptic number.

31649906 is a deficient number, since it is larger than the sum of its proper divisors (15824956).

31649906 is a wasteful number, since it uses less digits than its factorization.

31649906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15824955.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 31649906 is about 5625.8249172899. The cubic root of 31649906 is about 316.3181714963.

The spelling of 31649906 in words is "thirty-one million, six hundred forty-nine thousand, nine hundred six".