13275721 has 2 divisors, whose sum is σ = 13275722. Its totient is φ = 13275720.

The previous prime is 13275709. The next prime is 13275727. The reversal of 13275721 is 12757231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13220496 + 55225 = 3636^2 + 235^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13275721 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13275721.

It is not a weakly prime, because it can be changed into another prime (13275727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6637860 + 6637861.

It is an arithmetic number, because the mean of its divisors is an integer number (6637861).

Almost surely, 2^13275721 is an apocalyptic number.

It is an amenable number.

13275721 is a deficient number, since it is larger than the sum of its proper divisors (1).

13275721 is an equidigital number, since it uses as much as digits as its factorization.

13275721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2940, while the sum is 28.

The square root of 13275721 is about 3643.5862827714. The cubic root of 13275721 is about 236.7841923284.

The spelling of 13275721 in words is "thirteen million, two hundred seventy-five thousand, seven hundred twenty-one".