638807625 has 24 divisors (see below), whose sum is σ = 1151559240. Its totient is φ = 340696800.

The previous prime is 638807579. The next prime is 638807629. The reversal of 638807625 is 526708836.

638807625 is a `hidden beast` number, since 638 + 8 + 0 + 7 + 6 + 2 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 4372281 + 634435344 = 2091^2 + 25188^2 .

It is not a de Polignac number, because 638807625 - 2¹⁰ = 638806601 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (638807629) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282790 + ... + 285039.

It is an arithmetic number, because the mean of its divisors is an integer number (47981635).

Almost surely, 2^638807625 is an apocalyptic number.

It is an amenable number.

638807625 is a deficient number, since it is larger than the sum of its proper divisors (512751615).

638807625 is a wasteful number, since it uses less digits than its factorization.

638807625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 567850 (or 567837 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 638807625 is about 25274.6439144056. The cubic root of 638807625 is about 861.2383570391.

The spelling of 638807625 in words is "six hundred thirty-eight million, eight hundred seven thousand, six hundred twenty-five".