13266721 has 4 divisors (see below), whose sum is σ = 14287252. Its totient is φ = 12246192.

The previous prime is 13266697. The next prime is 13266727. The reversal of 13266721 is 12766231.

13266721 is digitally balanced in base 2, 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.

It can be written as a sum of positive squares in 2 ways, for example, as 1440000 + 11826721 = 1200^2 + 3439^2 .

It is a cyclic number.

It is not a de Polignac number, because 13266721 - 2¹¹ = 13264673 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 13266721.

It is not an unprimeable number, because it can be changed into a prime (13266727) 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, 510246 + ... + 510271.

It is an arithmetic number, because the mean of its divisors is an integer number (3571813).

Almost surely, 2^13266721 is an apocalyptic number.

It is an amenable number.

13266721 is a deficient number, since it is larger than the sum of its proper divisors (1020531).

13266721 is a wasteful number, since it uses less digits than its factorization.

13266721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1020530.

The product of its digits is 3024, while the sum is 28.

The square root of 13266721 is about 3642.3510264663. The cubic root of 13266721 is about 236.7306725866.

The spelling of 13266721 in words is "thirteen million, two hundred sixty-six thousand, seven hundred twenty-one".