638125692 has 24 divisors (see below), whose sum is σ = 1497283200. Its totient is φ = 211519536.

The previous prime is 638125679. The next prime is 638125693. The reversal of 638125692 is 296521836.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638125693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 146392 + ... + 150687.

It is an arithmetic number, because the mean of its divisors is an integer number (62386800).

Almost surely, 2^638125692 is an apocalyptic number.

It is an amenable number.

638125692 is an abundant number, since it is smaller than the sum of its proper divisors (859157508).

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

638125692 is a wasteful number, since it uses less digits than its factorization.

638125692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297265 (or 297263 counting only the distinct ones).

The product of its digits is 155520, while the sum is 42.

The square root of 638125692 is about 25261.1498550640. The cubic root of 638125692 is about 860.9317879758.

The spelling of 638125692 in words is "six hundred thirty-eight million, one hundred twenty-five thousand, six hundred ninety-two".