644003474 has 16 divisors (see below), whose sum is σ = 993686400. Its totient is φ = 312902160.

The previous prime is 644003449. The next prime is 644003489. The reversal of 644003474 is 474300446.

It is a self number, because there is not a number n which added to its sum of digits gives 644003474.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21674 + ... + 41925.

It is an arithmetic number, because the mean of its divisors is an integer number (62105400).

Almost surely, 2^644003474 is an apocalyptic number.

644003474 is a deficient number, since it is larger than the sum of its proper divisors (349682926).

644003474 is a wasteful number, since it uses less digits than its factorization.

644003474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63745.

The product of its (nonzero) digits is 32256, while the sum is 32.

The square root of 644003474 is about 25377.2235281955. The cubic root of 644003474 is about 863.5670636559.

The spelling of 644003474 in words is "six hundred forty-four million, three thousand, four hundred seventy-four".