12821261 has 2 divisors, whose sum is σ = 12821262. Its totient is φ = 12821260.

The previous prime is 12821227. The next prime is 12821273. The reversal of 12821261 is 16212821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7672900 + 5148361 = 2770^2 + 2269^2 .

It is a cyclic number.

It is not a de Polignac number, because 12821261 - 2¹⁴ = 12804877 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12821461) 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, 6410630 + 6410631.

It is an arithmetic number, because the mean of its divisors is an integer number (6410631).

Almost surely, 2^12821261 is an apocalyptic number.

It is an amenable number.

12821261 is a deficient number, since it is larger than the sum of its proper divisors (1).

12821261 is an equidigital number, since it uses as much as digits as its factorization.

12821261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 384, while the sum is 23.

The square root of 12821261 is about 3580.6788462525. The cubic root of 12821261 is about 234.0508631246.

The spelling of 12821261 in words is "twelve million, eight hundred twenty-one thousand, two hundred sixty-one".