12821279 has 4 divisors (see below), whose sum is σ = 12833400. Its totient is φ = 12809160.

The previous prime is 12821273. The next prime is 12821287. The reversal of 12821279 is 97212821.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12821279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12821273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4304 + ... + 6645.

It is an arithmetic number, because the mean of its divisors is an integer number (3208350).

Almost surely, 2^12821279 is an apocalyptic number.

12821279 is a deficient number, since it is larger than the sum of its proper divisors (12121).

12821279 is a wasteful number, since it uses less digits than its factorization.

12821279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12120.

The product of its digits is 4032, while the sum is 32.

The square root of 12821279 is about 3580.6813597415. The cubic root of 12821279 is about 234.0509726540.

The spelling of 12821279 in words is "twelve million, eight hundred twenty-one thousand, two hundred seventy-nine".