31644945 has 64 divisors (see below), whose sum is σ = 59616000. Its totient is φ = 15902208.

The previous prime is 31644931. The next prime is 31644961. The reversal of 31644945 is 54944613.

31644945 is a `hidden beast` number, since 3 + 1 + 644 + 9 + 4 + 5 = 666.

It is not a de Polignac number, because 31644945 - 2⁶ = 31644881 is a prime.

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 in 63 ways as a sum of consecutive naturals, for example, 230917 + ... + 231053.

It is an arithmetic number, because the mean of its divisors is an integer number (931500).

Almost surely, 2^31644945 is an apocalyptic number.

It is an amenable number.

31644945 is a deficient number, since it is larger than the sum of its proper divisors (27971055).

31644945 is a wasteful number, since it uses less digits than its factorization.

31644945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239 (or 233 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 31644945 is about 5625.3839868937. The cubic root of 31644945 is about 316.3016434172.

The spelling of 31644945 in words is "thirty-one million, six hundred forty-four thousand, nine hundred forty-five".