13575721 has 2 divisors, whose sum is σ = 13575722. Its totient is φ = 13575720.

The previous prime is 13575703. The next prime is 13575743. The reversal of 13575721 is 12757531.

13575721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10112400 + 3463321 = 3180^2 + 1861^2 .

It is a cyclic number.

It is not a de Polignac number, because 13575721 - 2⁵ = 13575689 is a prime.

It is not a weakly prime, because it can be changed into another prime (13575701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6787860 + 6787861.

It is an arithmetic number, because the mean of its divisors is an integer number (6787861).

Almost surely, 2^13575721 is an apocalyptic number.

It is an amenable number.

13575721 is a deficient number, since it is larger than the sum of its proper divisors (1).

13575721 is an equidigital number, since it uses as much as digits as its factorization.

13575721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7350, while the sum is 31.

The square root of 13575721 is about 3684.5245283483. The cubic root of 13575721 is about 238.5545117250.

The spelling of 13575721 in words is "thirteen million, five hundred seventy-five thousand, seven hundred twenty-one".