13239621 has 6 divisors (see below), whose sum is σ = 19123910. Its totient is φ = 8826408.

The previous prime is 13239619. The next prime is 13239641. The reversal of 13239621 is 12693231.

13239621 is a `hidden beast` number, since 1 + 3 + 2 + 39 + 621 = 666.

It can be written as a sum of positive squares in only one way, i.e., 13068225 + 171396 = 3615^2 + 414^2 .

It is not a de Polignac number, because 13239621 - 2¹ = 13239619 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 (13239641) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 735526 + ... + 735543.

Almost surely, 2^13239621 is an apocalyptic number.

It is an amenable number.

13239621 is a deficient number, since it is larger than the sum of its proper divisors (5884289).

13239621 is a wasteful number, since it uses less digits than its factorization.

13239621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1471075 (or 1471072 counting only the distinct ones).

The product of its digits is 1944, while the sum is 27.

The square root of 13239621 is about 3638.6290000493. The cubic root of 13239621 is about 236.5693723816.

The spelling of 13239621 in words is "thirteen million, two hundred thirty-nine thousand, six hundred twenty-one".