644053774 has 64 divisors (see below), whose sum is σ = 1264564224. Its totient is φ = 239031936.

The previous prime is 644053759. The next prime is 644053793. The reversal of 644053774 is 477350446.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 220407 + ... + 223309.

It is an arithmetic number, because the mean of its divisors is an integer number (19758816).

Almost surely, 2^644053774 is an apocalyptic number.

644053774 is a deficient number, since it is larger than the sum of its proper divisors (620510450).

644053774 is a wasteful number, since it uses less digits than its factorization.

644053774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3001.

The product of its (nonzero) digits is 282240, while the sum is 40.

The square root of 644053774 is about 25378.2145550076. The cubic root of 644053774 is about 863.5895460876.

The spelling of 644053774 in words is "six hundred forty-four million, fifty-three thousand, seven hundred seventy-four".