12736921 has 2 divisors, whose sum is σ = 12736922. Its totient is φ = 12736920.

The previous prime is 12736891. The next prime is 12736943. The reversal of 12736921 is 12963721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10368400 + 2368521 = 3220^2 + 1539^2 .

It is a cyclic number.

It is not a de Polignac number, because 12736921 - 2⁷ = 12736793 is a prime.

It is not a weakly prime, because it can be changed into another prime (12731921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6368460 + 6368461.

It is an arithmetic number, because the mean of its divisors is an integer number (6368461).

Almost surely, 2^12736921 is an apocalyptic number.

It is an amenable number.

12736921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12736921 is an equidigital number, since it uses as much as digits as its factorization.

12736921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 31.

The square root of 12736921 is about 3568.8823180374. The cubic root of 12736921 is about 233.5365275357.

The spelling of 12736921 in words is "twelve million, seven hundred thirty-six thousand, nine hundred twenty-one".