13136221 has 16 divisors (see below), whose sum is σ = 15669376. Its totient is φ = 10777536.

The previous prime is 13136203. The next prime is 13136231. The reversal of 13136221 is 12263131.

13136221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-13136221 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 (13136231) 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, 16975 + ... + 17731.

It is an arithmetic number, because the mean of its divisors is an integer number (979336).

Almost surely, 2^13136221 is an apocalyptic number.

It is an amenable number.

13136221 is a deficient number, since it is larger than the sum of its proper divisors (2533155).

13136221 is an equidigital number, since it uses as much as digits as its factorization.

13136221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 868.

The product of its digits is 216, while the sum is 19.

The square root of 13136221 is about 3624.3925008200. The cubic root of 13136221 is about 235.9519017655.

Adding to 13136221 its reverse (12263131), we get a palindrome (25399352).

The spelling of 13136221 in words is "thirteen million, one hundred thirty-six thousand, two hundred twenty-one".