644072346 has 48 divisors (see below), whose sum is σ = 1416542400. Its totient is φ = 211477824.

The previous prime is 644072329. The next prime is 644072383. The reversal of 644072346 is 643270446.

644072346 is a `hidden beast` number, since 644 + 0 + 7 + 2 + 3 + 4 + 6 = 666.

644072346 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 644072346.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 341835 + ... + 343713.

It is an arithmetic number, because the mean of its divisors is an integer number (29511300).

Almost surely, 2^644072346 is an apocalyptic number.

644072346 is an abundant number, since it is smaller than the sum of its proper divisors (772470054).

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

644072346 is a wasteful number, since it uses less digits than its factorization.

644072346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2163 (or 2160 counting only the distinct ones).

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

The square root of 644072346 is about 25378.5804567553. The cubic root of 644072346 is about 863.5978468598.

The spelling of 644072346 in words is "six hundred forty-four million, seventy-two thousand, three hundred forty-six".