12639400 has 24 divisors (see below), whose sum is σ = 29387070. Its totient is φ = 5055680.

The previous prime is 12639379. The next prime is 12639433. The reversal of 12639400 is 493621.

It can be written as a sum of positive squares in 3 ways, for example, as 12152196 + 487204 = 3486^2 + 698^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 31399 + ... + 31798.

Almost surely, 2^12639400 is an apocalyptic number.

12639400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12639400 is an abundant number, since it is smaller than the sum of its proper divisors (16747670).

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

12639400 is a wasteful number, since it uses less digits than its factorization.

12639400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63213 (or 63204 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 12639400 is about 3555.1933843323. The cubic root of 12639400 is about 232.9389710425.

The spelling of 12639400 in words is "twelve million, six hundred thirty-nine thousand, four hundred".