13582721 has 4 divisors (see below), whose sum is σ = 13593600. Its totient is φ = 13571844.

The previous prime is 13582693. The next prime is 13582727. The reversal of 13582721 is 12728531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12728531 = 2473 ⋅5147.

It is a cyclic number.

It is not a de Polignac number, because 13582721 - 2¹⁴ = 13566337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13582727) 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, 3281 + ... + 6158.

It is an arithmetic number, because the mean of its divisors is an integer number (3398400).

Almost surely, 2^13582721 is an apocalyptic number.

It is an amenable number.

13582721 is a deficient number, since it is larger than the sum of its proper divisors (10879).

13582721 is an equidigital number, since it uses as much as digits as its factorization.

13582721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10878.

The product of its digits is 3360, while the sum is 29.

The square root of 13582721 is about 3685.4743249682. The cubic root of 13582721 is about 238.5955063470.

The spelling of 13582721 in words is "thirteen million, five hundred eighty-two thousand, seven hundred twenty-one".