644052357 has 16 divisors (see below), whose sum is σ = 1027548480. Its totient is φ = 396339696.

The previous prime is 644052347. The next prime is 644052389. The reversal of 644052357 is 753250446.

644052357 is a `hidden beast` number, since 644 + 0 + 5 + 2 + 3 + 5 + 7 = 666.

644052357 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 644052357 - 2⁴ = 644052341 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644052347) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 917103 + ... + 917804.

It is an arithmetic number, because the mean of its divisors is an integer number (64221780).

Almost surely, 2^644052357 is an apocalyptic number.

It is an amenable number.

644052357 is a deficient number, since it is larger than the sum of its proper divisors (383496123).

644052357 is a wasteful number, since it uses less digits than its factorization.

644052357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1834929 (or 1834923 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

The square root of 644052357 is about 25378.1866373466. The cubic root of 644052357 is about 863.5889127516.

The spelling of 644052357 in words is "six hundred forty-four million, fifty-two thousand, three hundred fifty-seven".