13226821 has 2 divisors, whose sum is σ = 13226822. Its totient is φ = 13226820.

The previous prime is 13226819. The next prime is 13226827. The reversal of 13226821 is 12862231.

13226821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12040900 + 1185921 = 3470^2 + 1089^2 .

It is an emirp because it is prime and its reverse (12862231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13226821 - 2¹ = 13226819 is a prime.

Together with 13226819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13226827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6613410 + 6613411.

It is an arithmetic number, because the mean of its divisors is an integer number (6613411).

Almost surely, 2^13226821 is an apocalyptic number.

It is an amenable number.

13226821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13226821 is an equidigital number, since it uses as much as digits as its factorization.

13226821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 25.

The square root of 13226821 is about 3636.8696704721. The cubic root of 13226821 is about 236.4931097671.

The spelling of 13226821 in words is "thirteen million, two hundred twenty-six thousand, eight hundred twenty-one".