644410544053640 has 64 divisors (see below), whose sum is σ = 1784521506620160. Its totient is φ = 203945315040000.

The previous prime is 644410544053609. The next prime is 644410544053687. The reversal of 644410544053640 is 46350445014446.

It is a super-3 number, since 3×644410544053640³ (a number of 45 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88517928236 + ... + 88517935515.

It is an arithmetic number, because the mean of its divisors is an integer number (27883148540940).

Almost surely, 2^{644410544053640} is an apocalyptic number.

It is an amenable number.

644410544053640 is an abundant number, since it is smaller than the sum of its proper divisors (1140110962566520).

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

644410544053640 is a wasteful number, since it uses less digits than its factorization.

644410544053640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177035863782 (or 177035863778 counting only the distinct ones).

The product of its (nonzero) digits is 11059200, while the sum is 50.

The spelling of 644410544053640 in words is "six hundred forty-four trillion, four hundred ten billion, five hundred forty-four million, fifty-three thousand, six hundred forty".