638678212824 has 16 divisors (see below), whose sum is σ = 1596695532120. Its totient is φ = 212892737600.

The previous prime is 638678212811. The next prime is 638678212849. The reversal of 638678212824 is 428212876836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13305796077 + ... + 13305796124.

Almost surely, 2^638678212824 is an apocalyptic number.

It is an amenable number.

638678212824 is an abundant number, since it is smaller than the sum of its proper divisors (958017319296).

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

638678212824 is a wasteful number, since it uses less digits than its factorization.

638678212824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26611592210 (or 26611592206 counting only the distinct ones).

The product of its digits is 12386304, while the sum is 57.

The spelling of 638678212824 in words is "six hundred thirty-eight billion, six hundred seventy-eight million, two hundred twelve thousand, eight hundred twenty-four".