12561331 has 2 divisors, whose sum is σ = 12561332. Its totient is φ = 12561330.

The previous prime is 12561323. The next prime is 12561349. The reversal of 12561331 is 13316521.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (13316521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12561331 - 2³ = 12561323 is a prime.

It is a super-2 number, since 2×12561331² = 315574072983122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12561301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6280665 + 6280666.

It is an arithmetic number, because the mean of its divisors is an integer number (6280666).

Almost surely, 2^12561331 is an apocalyptic number.

12561331 is a deficient number, since it is larger than the sum of its proper divisors (1).

12561331 is an equidigital number, since it uses as much as digits as its factorization.

12561331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 22.

The square root of 12561331 is about 3544.1968060479. The cubic root of 12561331 is about 232.4583869719.

Adding to 12561331 its reverse (13316521), we get a palindrome (25877852).

The spelling of 12561331 in words is "twelve million, five hundred sixty-one thousand, three hundred thirty-one".