12403921 has 2 divisors, whose sum is σ = 12403922. Its totient is φ = 12403920.

The previous prime is 12403901. The next prime is 12403933. The reversal of 12403921 is 12930421.

12403921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9235521 + 3168400 = 3039^2 + 1780^2 .

It is a cyclic number.

It is not a de Polignac number, because 12403921 - 2⁵ = 12403889 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12403892 and 12403901.

It is not a weakly prime, because it can be changed into another prime (12403901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6201960 + 6201961.

It is an arithmetic number, because the mean of its divisors is an integer number (6201961).

Almost surely, 2^12403921 is an apocalyptic number.

It is an amenable number.

12403921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12403921 is an equidigital number, since it uses as much as digits as its factorization.

12403921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 12403921 is about 3521.9200729148. The cubic root of 12403921 is about 231.4832993968.

The spelling of 12403921 in words is "twelve million, four hundred three thousand, nine hundred twenty-one".