638126375 has 16 divisors (see below), whose sum is σ = 831010752. Its totient is φ = 488303200.

The previous prime is 638126369. The next prime is 638126387. The reversal of 638126375 is 573621836.

It is a de Polignac number, because none of the positive numbers 2^k-638126375 is a prime.

It is a super-3 number, since 3×638126375³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108104 + ... + 113853.

It is an arithmetic number, because the mean of its divisors is an integer number (51938172).

Almost surely, 2^638126375 is an apocalyptic number.

638126375 is a deficient number, since it is larger than the sum of its proper divisors (192884377).

638126375 is a wasteful number, since it uses less digits than its factorization.

638126375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221995 (or 221985 counting only the distinct ones).

The product of its digits is 181440, while the sum is 41.

The square root of 638126375 is about 25261.1633738433. The cubic root of 638126375 is about 860.9320951337.

The spelling of 638126375 in words is "six hundred thirty-eight million, one hundred twenty-six thousand, three hundred seventy-five".