13382721 has 18 divisors (see below), whose sum is σ = 21249410. Its totient is φ = 8110080.

The previous prime is 13382683. The next prime is 13382737. The reversal of 13382721 is 12728331.

It can be written as a sum of positive squares in only one way, i.e., 12702096 + 680625 = 3564^2 + 825^2 .

It is not a de Polignac number, because 13382721 - 2⁶ = 13382657 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13382741) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5056 + ... + 7233.

Almost surely, 2^13382721 is an apocalyptic number.

13382721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13382721 is a deficient number, since it is larger than the sum of its proper divisors (7866689).

13382721 is a wasteful number, since it uses less digits than its factorization.

13382721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12317 (or 12303 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 13382721 is about 3658.2401506735. The cubic root of 13382721 is about 237.4186373193.

The spelling of 13382721 in words is "thirteen million, three hundred eighty-two thousand, seven hundred twenty-one".