13621639 has 8 divisors (see below), whose sum is σ = 13813760. Its totient is φ = 13431096.

The previous prime is 13621637. The next prime is 13621649. The reversal of 13621639 is 93612631.

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 13621639 - 2¹ = 13621637 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13621639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13621631) 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, 35752 + ... + 36130.

It is an arithmetic number, because the mean of its divisors is an integer number (1726720).

Almost surely, 2^13621639 is an apocalyptic number.

13621639 is a deficient number, since it is larger than the sum of its proper divisors (192121).

13621639 is a wasteful number, since it uses less digits than its factorization.

13621639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789.

The product of its digits is 5832, while the sum is 31.

The square root of 13621639 is about 3690.7504656912. The cubic root of 13621639 is about 238.8231682763.

The spelling of 13621639 in words is "thirteen million, six hundred twenty-one thousand, six hundred thirty-nine".