13638913 has 8 divisors (see below), whose sum is σ = 14505480. Its totient is φ = 12779520.

The previous prime is 13638907. The next prime is 13638943. The reversal of 13638913 is 31983631.

It can be written as a sum of positive squares in 4 ways, for example, as 4566769 + 9072144 = 2137^2 + 3012^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13638913 - 2⁵ = 13638881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13638943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2433 + ... + 5761.

It is an arithmetic number, because the mean of its divisors is an integer number (1813185).

Almost surely, 2^13638913 is an apocalyptic number.

It is an amenable number.

13638913 is a deficient number, since it is larger than the sum of its proper divisors (866567).

13638913 is a wasteful number, since it uses less digits than its factorization.

13638913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3587.

The product of its digits is 11664, while the sum is 34.

The square root of 13638913 is about 3693.0898987162. The cubic root of 13638913 is about 238.9240785210.

The spelling of 13638913 in words is "thirteen million, six hundred thirty-eight thousand, nine hundred thirteen".