638496151820 has 24 divisors (see below), whose sum is σ = 1340978998128. Its totient is φ = 255372350400.

The previous prime is 638496151781. The next prime is 638496151823. The reversal of 638496151820 is 28151694836.

It is not an unprimeable number, because it can be changed into a prime (638496151823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1430771 + ... + 1823210.

It is an arithmetic number, because the mean of its divisors is an integer number (55874124922).

Almost surely, 2^638496151820 is an apocalyptic number.

It is an amenable number.

638496151820 is an abundant number, since it is smaller than the sum of its proper divisors (702482846308).

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

638496151820 is a wasteful number, since it uses less digits than its factorization.

638496151820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3263801 (or 3263799 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 53.

The spelling of 638496151820 in words is "six hundred thirty-eight billion, four hundred ninety-six million, one hundred fifty-one thousand, eight hundred twenty".