12456921 has 16 divisors (see below), whose sum is σ = 17328960. Its totient is φ = 7949760.

The previous prime is 12456911. The next prime is 12456929. The reversal of 12456921 is 12965421.

It is not a de Polignac number, because 12456921 - 2¹⁰ = 12455897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12456929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10851 + ... + 11943.

It is an arithmetic number, because the mean of its divisors is an integer number (1083060).

Almost surely, 2^12456921 is an apocalyptic number.

It is an amenable number.

12456921 is a deficient number, since it is larger than the sum of its proper divisors (4872039).

12456921 is a wasteful number, since it uses less digits than its factorization.

12456921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1256.

The product of its digits is 4320, while the sum is 30.

The square root of 12456921 is about 3529.4363572673. The cubic root of 12456921 is about 231.8125281484.

The spelling of 12456921 in words is "twelve million, four hundred fifty-six thousand, nine hundred twenty-one".