12641921 has 4 divisors (see below), whose sum is σ = 12815172. Its totient is φ = 12468672.

The previous prime is 12641917. The next prime is 12641963. The reversal of 12641921 is 12914621.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10857025 + 1784896 = 3295^2 + 1336^2 .

It is a cyclic number.

It is not a de Polignac number, because 12641921 - 2² = 12641917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12641971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86516 + ... + 86661.

It is an arithmetic number, because the mean of its divisors is an integer number (3203793).

Almost surely, 2^12641921 is an apocalyptic number.

It is an amenable number.

12641921 is a deficient number, since it is larger than the sum of its proper divisors (173251).

12641921 is an equidigital number, since it uses as much as digits as its factorization.

12641921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173250.

The product of its digits is 864, while the sum is 26.

The square root of 12641921 is about 3555.5479183946. The cubic root of 12641921 is about 232.9544570125.

The spelling of 12641921 in words is "twelve million, six hundred forty-one thousand, nine hundred twenty-one".