13686621 has 16 divisors (see below), whose sum is σ = 19782336. Its totient is φ = 8366976.

The previous prime is 13686619. The next prime is 13686641. The reversal of 13686621 is 12668631.

It is not a de Polignac number, because 13686621 - 2¹ = 13686619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13686641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5281 + ... + 7433.

It is an arithmetic number, because the mean of its divisors is an integer number (1236396).

Almost surely, 2^13686621 is an apocalyptic number.

It is an amenable number.

13686621 is a deficient number, since it is larger than the sum of its proper divisors (6095715).

13686621 is a wasteful number, since it uses less digits than its factorization.

13686621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2332.

The product of its digits is 10368, while the sum is 33.

The square root of 13686621 is about 3699.5433501988. The cubic root of 13686621 is about 239.2023344496.

The spelling of 13686621 in words is "thirteen million, six hundred eighty-six thousand, six hundred twenty-one".