644608514 has 16 divisors (see below), whose sum is σ = 1058260896. Its totient is φ = 292046400.

The previous prime is 644608507. The next prime is 644608579. The reversal of 644608514 is 415806446.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40967 + ... + 54474.

It is an arithmetic number, because the mean of its divisors is an integer number (66141306).

Almost surely, 2^644608514 is an apocalyptic number.

644608514 is a deficient number, since it is larger than the sum of its proper divisors (413652382).

644608514 is a wasteful number, since it uses less digits than its factorization.

644608514 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95761.

The product of its (nonzero) digits is 92160, while the sum is 38.

The square root of 644608514 is about 25389.1416554400. The cubic root of 644608514 is about 863.8374188613.

The spelling of 644608514 in words is "six hundred forty-four million, six hundred eight thousand, five hundred fourteen".