644507302648 has 16 divisors (see below), whose sum is σ = 1318310391960. Its totient is φ = 292957864800.

The previous prime is 644507302583. The next prime is 644507302679. The reversal of 644507302648 is 846203705446.

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, 3661973223 + ... + 3661973398.

Almost surely, 2^644507302648 is an apocalyptic number.

It is an amenable number.

644507302648 is an abundant number, since it is smaller than the sum of its proper divisors (673803089312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644507302648 is a wasteful number, since it uses less digits than its factorization.

644507302648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7323946638 (or 7323946634 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 49.

The spelling of 644507302648 in words is "six hundred forty-four billion, five hundred seven million, three hundred two thousand, six hundred forty-eight".