644557148 has 12 divisors (see below), whose sum is σ = 1128512112. Its totient is φ = 322125120.

The previous prime is 644557127. The next prime is 644557153. The reversal of 644557148 is 841755446.

644557148 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 644557099 and 644557108.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28640 + ... + 45927.

It is an arithmetic number, because the mean of its divisors is an integer number (94042676).

Almost surely, 2^644557148 is an apocalyptic number.

It is an amenable number.

644557148 is a deficient number, since it is larger than the sum of its proper divisors (483954964).

644557148 is a wasteful number, since it uses less digits than its factorization.

644557148 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76732 (or 76730 counting only the distinct ones).

The product of its digits is 537600, while the sum is 44.

The square root of 644557148 is about 25388.1300611132. The cubic root of 644557148 is about 863.8144731247.

The spelling of 644557148 in words is "six hundred forty-four million, five hundred fifty-seven thousand, one hundred forty-eight".