638256616 has 16 divisors (see below), whose sum is σ = 1222194240. Its totient is φ = 312338160.

The previous prime is 638256587. The next prime is 638256649. The reversal of 638256616 is 616652836.

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, 848370 + ... + 849121.

It is an arithmetic number, because the mean of its divisors is an integer number (76387140).

Almost surely, 2^638256616 is an apocalyptic number.

It is an amenable number.

638256616 is a deficient number, since it is larger than the sum of its proper divisors (583937624).

638256616 is a wasteful number, since it uses less digits than its factorization.

638256616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1697544 (or 1697540 counting only the distinct ones).

The product of its digits is 311040, while the sum is 43.

The square root of 638256616 is about 25263.7411323026. The cubic root of 638256616 is about 860.9906629628.

The spelling of 638256616 in words is "six hundred thirty-eight million, two hundred fifty-six thousand, six hundred sixteen".