12638557 has 4 divisors (see below), whose sum is σ = 12646656. Its totient is φ = 12630460.

The previous prime is 12638551. The next prime is 12638581. The reversal of 12638557 is 75583621.

12638557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 75583621 = 967 ⋅78163.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12638557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 883 + ... + 5104.

It is an arithmetic number, because the mean of its divisors is an integer number (3161664).

Almost surely, 2^12638557 is an apocalyptic number.

It is an amenable number.

12638557 is a deficient number, since it is larger than the sum of its proper divisors (8099).

12638557 is an equidigital number, since it uses as much as digits as its factorization.

12638557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8098.

The product of its digits is 50400, while the sum is 37.

The square root of 12638557 is about 3555.0748234039. The cubic root of 12638557 is about 232.9337922123.

It can be divided in two parts, 126 and 38557, that added together give a palindrome (38683).

The spelling of 12638557 in words is "twelve million, six hundred thirty-eight thousand, five hundred fifty-seven".