638879460 has 48 divisors (see below), whose sum is σ = 1826931456. Its totient is φ = 166742272.

The previous prime is 638879447. The next prime is 638879467. The reversal of 638879460 is 64978836.

It is not an unprimeable number, because it can be changed into a prime (638879467) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110457 + ... + 116096.

It is an arithmetic number, because the mean of its divisors is an integer number (38061072).

Almost surely, 2^638879460 is an apocalyptic number.

638879460 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

638879460 is an abundant number, since it is smaller than the sum of its proper divisors (1188051996).

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

638879460 is a wasteful number, since it uses less digits than its factorization.

638879460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226612 (or 226610 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 51.

The square root of 638879460 is about 25276.0649627271. The cubic root of 638879460 is about 861.2706384000.

The spelling of 638879460 in words is "six hundred thirty-eight million, eight hundred seventy-nine thousand, four hundred sixty".