644306274 has 24 divisors (see below), whose sum is σ = 1396764720. Its totient is φ = 214650648.

The previous prime is 644306251. The next prime is 644306287. The reversal of 644306274 is 472603446.

644306274 is a `hidden beast` number, since 644 + 3 + 0 + 6 + 2 + 7 + 4 = 666.

644306274 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27657 + ... + 45315.

It is an arithmetic number, because the mean of its divisors is an integer number (58198530).

Almost surely, 2^644306274 is an apocalyptic number.

644306274 is an abundant number, since it is smaller than the sum of its proper divisors (752458446).

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

644306274 is a wasteful number, since it uses less digits than its factorization.

644306274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19694 (or 19691 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 36.

The square root of 644306274 is about 25383.1888067674. The cubic root of 644306274 is about 863.7023875299.

The spelling of 644306274 in words is "six hundred forty-four million, three hundred six thousand, two hundred seventy-four".