13638656 has 44 divisors (see below), whose sum is σ = 28739880. Its totient is φ = 6451200.

The previous prime is 13638629. The next prime is 13638659. The reversal of 13638656 is 65683631.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

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 (13638659) 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, 19106 + ... + 19806.

Almost surely, 2^13638656 is an apocalyptic number.

13638656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13638656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14369940).

13638656 is an abundant number, since it is smaller than the sum of its proper divisors (15101224).

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

13638656 is an equidigital number, since it uses as much as digits as its factorization.

13638656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740 (or 722 counting only the distinct ones).

The product of its digits is 77760, while the sum is 38.

The square root of 13638656 is about 3693.0551038402. The cubic root of 13638656 is about 238.9225778180.

The spelling of 13638656 in words is "thirteen million, six hundred thirty-eight thousand, six hundred fifty-six".