638825107 has 2 divisors, whose sum is σ = 638825108. Its totient is φ = 638825106.

The previous prime is 638825053. The next prime is 638825171. The reversal of 638825107 is 701528836.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638825107 is a prime.

It is a super-2 number, since 2×638825107² = 816195034667122898, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 638825107.

It is not a weakly prime, because it can be changed into another prime (638825177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319412553 + 319412554.

It is an arithmetic number, because the mean of its divisors is an integer number (319412554).

Almost surely, 2^638825107 is an apocalyptic number.

638825107 is a deficient number, since it is larger than the sum of its proper divisors (1).

638825107 is an equidigital number, since it uses as much as digits as its factorization.

638825107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 638825107 is about 25274.9897527180. The cubic root of 638825107 is about 861.2462133592.

The spelling of 638825107 in words is "six hundred thirty-eight million, eight hundred twenty-five thousand, one hundred seven".