638632404 has 96 divisors (see below), whose sum is σ = 1786458240. Its totient is φ = 196545024.

The previous prime is 638632373. The next prime is 638632411. The reversal of 638632404 is 404236836.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 94027 + ... + 100589.

It is an arithmetic number, because the mean of its divisors is an integer number (18608940).

Almost surely, 2^638632404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638632404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (893229120).

638632404 is an abundant number, since it is smaller than the sum of its proper divisors (1147825836).

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

638632404 is a wasteful number, since it uses less digits than its factorization.

638632404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6646 (or 6638 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 36.

The square root of 638632404 is about 25271.1773370375. The cubic root of 638632404 is about 861.1596057114.

The spelling of 638632404 in words is "six hundred thirty-eight million, six hundred thirty-two thousand, four hundred four".