13649221 has 4 divisors (see below), whose sum is σ = 13661100. Its totient is φ = 13637344.

The previous prime is 13649213. The next prime is 13649231. The reversal of 13649221 is 12294631.

13649221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12294631 = 31 ⋅396601.

It can be written as a sum of positive squares in 2 ways, for example, as 6305121 + 7344100 = 2511^2 + 2710^2 .

It is a cyclic number.

It is not a de Polignac number, because 13649221 - 2³ = 13649213 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 13649221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13649231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4006 + ... + 6583.

It is an arithmetic number, because the mean of its divisors is an integer number (3415275).

Almost surely, 2^13649221 is an apocalyptic number.

It is an amenable number.

13649221 is a deficient number, since it is larger than the sum of its proper divisors (11879).

13649221 is a wasteful number, since it uses less digits than its factorization.

13649221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11878.

The product of its digits is 2592, while the sum is 28.

The square root of 13649221 is about 3694.4852144785. The cubic root of 13649221 is about 238.9842546072.

It can be divided in two parts, 1364 and 9221, that added together give a triangular number (10585 = T₁₄₅).

The spelling of 13649221 in words is "thirteen million, six hundred forty-nine thousand, two hundred twenty-one".