644962952 has 32 divisors (see below), whose sum is σ = 1250726400. Its totient is φ = 311610624.

The previous prime is 644962951. The next prime is 644962963. The reversal of 644962952 is 259269446.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a junction number, because it is equal to n+sod(n) for n = 644962897 and 644962906.

It is not an unprimeable number, because it can be changed into a prime (644962951) 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 in 7 ways as a sum of consecutive naturals, for example, 18848 + ... + 40560.

It is an arithmetic number, because the mean of its divisors is an integer number (39085200).

Almost surely, 2^644962952 is an apocalyptic number.

It is an amenable number.

644962952 is a deficient number, since it is larger than the sum of its proper divisors (605763448).

644962952 is a wasteful number, since it uses less digits than its factorization.

644962952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21845 (or 21841 counting only the distinct ones).

The product of its digits is 933120, while the sum is 47.

The square root of 644962952 is about 25396.1208061389. The cubic root of 644962952 is about 863.9957168569.

The spelling of 644962952 in words is "six hundred forty-four million, nine hundred sixty-two thousand, nine hundred fifty-two".