13221881 has 2 divisors, whose sum is σ = 13221882. Its totient is φ = 13221880.

The previous prime is 13221877. The next prime is 13221911. The reversal of 13221881 is 18812231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12709225 + 512656 = 3565^2 + 716^2 .

It is a cyclic number.

It is not a de Polignac number, because 13221881 - 2² = 13221877 is a prime.

It is a super-2 number, since 2×13221881² = 349636274356322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 13221881.

It is not a weakly prime, because it can be changed into another prime (13221821) 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, 6610940 + 6610941.

It is an arithmetic number, because the mean of its divisors is an integer number (6610941).

Almost surely, 2^13221881 is an apocalyptic number.

It is an amenable number.

13221881 is a deficient number, since it is larger than the sum of its proper divisors (1).

13221881 is an equidigital number, since it uses as much as digits as its factorization.

13221881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 768, while the sum is 26.

The square root of 13221881 is about 3636.1904515578. The cubic root of 13221881 is about 236.4636640060.

The spelling of 13221881 in words is "thirteen million, two hundred twenty-one thousand, eight hundred eighty-one".