12791521 has 4 divisors (see below), whose sum is σ = 12856000. Its totient is φ = 12727044.

The previous prime is 12791489. The next prime is 12791533. The reversal of 12791521 is 12519721.

12791521 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12791521 - 2⁵ = 12791489 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 12791521.

It is not an unprimeable number, because it can be changed into a prime (12791591) 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, 31941 + ... + 32338.

It is an arithmetic number, because the mean of its divisors is an integer number (3214000).

Almost surely, 2^12791521 is an apocalyptic number.

It is an amenable number.

12791521 is a deficient number, since it is larger than the sum of its proper divisors (64479).

12791521 is an equidigital number, since it uses as much as digits as its factorization.

12791521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64478.

The product of its digits is 1260, while the sum is 28.

The square root of 12791521 is about 3576.5235914223. The cubic root of 12791521 is about 233.8697560928.

The spelling of 12791521 in words is "twelve million, seven hundred ninety-one thousand, five hundred twenty-one".