638135616 has 28 divisors (see below), whose sum is σ = 1688400992. Its totient is φ = 212711808.

The previous prime is 638135593. The next prime is 638135627. The reversal of 638135616 is 616531836.

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, 1661620 + ... + 1662003.

Almost surely, 2^638135616 is an apocalyptic number.

It is an amenable number.

638135616 is an abundant number, since it is smaller than the sum of its proper divisors (1050265376).

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

638135616 is a wasteful number, since it uses less digits than its factorization.

638135616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3323638 (or 3323628 counting only the distinct ones).

The product of its digits is 77760, while the sum is 39.

The square root of 638135616 is about 25261.3462824134. The cubic root of 638135616 is about 860.9362509642.

The spelling of 638135616 in words is "six hundred thirty-eight million, one hundred thirty-five thousand, six hundred sixteen".