644601052 has 24 divisors (see below), whose sum is σ = 1173807936. Its totient is φ = 309486528.

The previous prime is 644601043. The next prime is 644601071. The reversal of 644601052 is 250106446.

It is a self number, because there is not a number n which added to its sum of digits gives 644601052.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22383 + ... + 42310.

It is an arithmetic number, because the mean of its divisors is an integer number (48908664).

Almost surely, 2^644601052 is an apocalyptic number.

It is an amenable number.

644601052 is a deficient number, since it is larger than the sum of its proper divisors (529206884).

644601052 is a wasteful number, since it uses less digits than its factorization.

644601052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64797 (or 64795 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 644601052 is about 25388.9947024296. The cubic root of 644601052 is about 863.8340855825.

Adding to 644601052 its reverse (250106446), we get a palindrome (894707498).

The spelling of 644601052 in words is "six hundred forty-four million, six hundred one thousand, fifty-two".