638814460 has 24 divisors (see below), whose sum is σ = 1342007856. Its totient is φ = 255431040.

The previous prime is 638814439. The next prime is 638814487. The reversal of 638814460 is 64418836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79215 + ... + 86905.

It is an arithmetic number, because the mean of its divisors is an integer number (55916994).

Almost surely, 2^638814460 is an apocalyptic number.

It is an amenable number.

638814460 is an abundant number, since it is smaller than the sum of its proper divisors (703193396).

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

638814460 is a wasteful number, since it uses less digits than its factorization.

638814460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11853 (or 11851 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 638814460 is about 25274.7791286096. The cubic root of 638814460 is about 861.2414286697.

The spelling of 638814460 in words is "six hundred thirty-eight million, eight hundred fourteen thousand, four hundred sixty".