638820345604 has 48 divisors (see below), whose sum is σ = 1301989852800. Its totient is φ = 268564398336.

The previous prime is 638820345593. The next prime is 638820345619. The reversal of 638820345604 is 406543028836.

It is a super-2 number, since 2×638820345604² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8538792 + ... + 8613280.

It is an arithmetic number, because the mean of its divisors is an integer number (27124788600).

Almost surely, 2^638820345604 is an apocalyptic number.

It is an amenable number.

638820345604 is an abundant number, since it is smaller than the sum of its proper divisors (663169507196).

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

638820345604 is a wasteful number, since it uses less digits than its factorization.

638820345604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80332 (or 80330 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 49.

The spelling of 638820345604 in words is "six hundred thirty-eight billion, eight hundred twenty million, three hundred forty-five thousand, six hundred four".