639804224 has 28 divisors (see below), whose sum is σ = 1299142944. Its totient is φ = 312461184.

The previous prime is 639804223. The next prime is 639804229. The reversal of 639804224 is 422408936.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639804223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113492 + ... + 118995.

Almost surely, 2^639804224 is an apocalyptic number.

639804224 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

639804224 is an abundant number, since it is smaller than the sum of its proper divisors (659338720).

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

639804224 is a wasteful number, since it uses less digits than its factorization.

639804224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232542 (or 232532 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 639804224 is about 25294.3516224473. The cubic root of 639804224 is about 861.6859948416.

The spelling of 639804224 in words is "six hundred thirty-nine million, eight hundred four thousand, two hundred twenty-four".