644030732 has 24 divisors (see below), whose sum is σ = 1158670464. Its totient is φ = 312999552.

The previous prime is 644030713. The next prime is 644030743. The reversal of 644030732 is 237030446.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 644030695 and 644030704.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 230528 + ... + 233304.

It is an arithmetic number, because the mean of its divisors is an integer number (48277936).

Almost surely, 2^644030732 is an apocalyptic number.

It is an amenable number.

644030732 is a deficient number, since it is larger than the sum of its proper divisors (514639732).

644030732 is a wasteful number, since it uses less digits than its factorization.

644030732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4385 (or 4383 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 29.

The square root of 644030732 is about 25377.7605789006. The cubic root of 644030732 is about 863.5792472231.

The spelling of 644030732 in words is "six hundred forty-four million, thirty thousand, seven hundred thirty-two".