12591421 has 2 divisors, whose sum is σ = 12591422. Its totient is φ = 12591420.

The previous prime is 12591413. The next prime is 12591427. The reversal of 12591421 is 12419521.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12355225 + 236196 = 3515^2 + 486^2 .

It is a cyclic number.

It is not a de Polignac number, because 12591421 - 2³ = 12591413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12591427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6295710 + 6295711.

It is an arithmetic number, because the mean of its divisors is an integer number (6295711).

Almost surely, 2^12591421 is an apocalyptic number.

It is an amenable number.

12591421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12591421 is an equidigital number, since it uses as much as digits as its factorization.

12591421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 720, while the sum is 25.

The square root of 12591421 is about 3548.4392343677. The cubic root of 12591421 is about 232.6438528582.

The spelling of 12591421 in words is "twelve million, five hundred ninety-one thousand, four hundred twenty-one".