12638990 has 128 divisors (see below), whose sum is σ = 31933440. Its totient is φ = 3483648.

The previous prime is 12638987. The next prime is 12638993. The reversal of 12638990 is 9983621.

It is an interprime number because it is at equal distance from previous prime (12638987) and next prime (12638993).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638993) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 293909 + ... + 293951.

It is an arithmetic number, because the mean of its divisors is an integer number (249480).

Almost surely, 2^12638990 is an apocalyptic number.

12638990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12638990 is an abundant number, since it is smaller than the sum of its proper divisors (19294450).

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

12638990 is a wasteful number, since it uses less digits than its factorization.

12638990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 12638990 is about 3555.1357217412. The cubic root of 12638990 is about 232.9364523045.

The spelling of 12638990 in words is "twelve million, six hundred thirty-eight thousand, nine hundred ninety".