638432625 has 32 divisors (see below), whose sum is σ = 1072730880. Its totient is φ = 337171200.

The previous prime is 638432621. The next prime is 638432633. The reversal of 638432625 is 526234836.

It is a happy number.

638432625 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 638432625 - 2² = 638432621 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (638432621) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30361 + ... + 46889.

It is an arithmetic number, because the mean of its divisors is an integer number (33522840).

Almost surely, 2^638432625 is an apocalyptic number.

It is an amenable number.

638432625 is a deficient number, since it is larger than the sum of its proper divisors (434298255).

638432625 is a wasteful number, since it uses less digits than its factorization.

638432625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16650 (or 16640 counting only the distinct ones).

The product of its digits is 207360, while the sum is 39.

The square root of 638432625 is about 25267.2243232216. The cubic root of 638432625 is about 861.0697994595.

The spelling of 638432625 in words is "six hundred thirty-eight million, four hundred thirty-two thousand, six hundred twenty-five".