644340272 has 20 divisors (see below), whose sum is σ = 1249699776. Its totient is φ = 321837120.

The previous prime is 644340253. The next prime is 644340283. The reversal of 644340272 is 272043446.

644340272 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×644340272² = 830348772242067968, which contains 22 as substring.

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, 4463 + ... + 36174.

Almost surely, 2^644340272 is an apocalyptic number.

It is an amenable number.

644340272 is a deficient number, since it is larger than the sum of its proper divisors (605359504).

644340272 is a wasteful number, since it uses less digits than its factorization.

644340272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41636 (or 41630 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 32.

The square root of 644340272 is about 25383.8584931448. The cubic root of 644340272 is about 863.7175788753.

The spelling of 644340272 in words is "six hundred forty-four million, three hundred forty thousand, two hundred seventy-two".