12981821 has 8 divisors (see below), whose sum is σ = 14014080. Its totient is φ = 11988592.

The previous prime is 12981803. The next prime is 12981827. The reversal of 12981821 is 12818921.

12981821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12981821 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 (12981827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9065 + ... + 10398.

It is an arithmetic number, because the mean of its divisors is an integer number (1751760).

Almost surely, 2^12981821 is an apocalyptic number.

It is an amenable number.

12981821 is a deficient number, since it is larger than the sum of its proper divisors (1032259).

12981821 is a wasteful number, since it uses less digits than its factorization.

12981821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19515.

The product of its digits is 2304, while the sum is 32.

The square root of 12981821 is about 3603.0294198077. The cubic root of 12981821 is about 235.0238153018.

The spelling of 12981821 in words is "twelve million, nine hundred eighty-one thousand, eight hundred twenty-one".