12779521 has 4 divisors (see below), whose sum is σ = 12871600. Its totient is φ = 12687444.

The previous prime is 12779483. The next prime is 12779531. The reversal of 12779521 is 12597721.

12779521 is digitally balanced in base 3, 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, and also an emirpimes, since its reverse is a distinct semiprime: 12597721 = 23 ⋅547727.

It is a cyclic number.

It is not a de Polignac number, because 12779521 - 2¹¹ = 12777473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12779531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45831 + ... + 46108.

It is an arithmetic number, because the mean of its divisors is an integer number (3217900).

It is a Proth number, since it is equal to 195 ⋅ 2¹⁶ + 1 and 195 < 2¹⁶.

Almost surely, 2^12779521 is an apocalyptic number.

It is an amenable number.

12779521 is a deficient number, since it is larger than the sum of its proper divisors (92079).

12779521 is an equidigital number, since it uses as much as digits as its factorization.

12779521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92078.

The product of its digits is 8820, while the sum is 34.

The square root of 12779521 is about 3574.8455910710. The cubic root of 12779521 is about 233.7966004682.

The spelling of 12779521 in words is "twelve million, seven hundred seventy-nine thousand, five hundred twenty-one".