13221647 has 2 divisors, whose sum is σ = 13221648. Its totient is φ = 13221646.

The previous prime is 13221643. The next prime is 13221667. The reversal of 13221647 is 74612231.

It is a weak prime.

It is an emirp because it is prime and its reverse (74612231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13221647 - 2² = 13221643 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13221641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6610823 + 6610824.

It is an arithmetic number, because the mean of its divisors is an integer number (6610824).

Almost surely, 2^13221647 is an apocalyptic number.

13221647 is a deficient number, since it is larger than the sum of its proper divisors (1).

13221647 is an equidigital number, since it uses as much as digits as its factorization.

13221647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 26.

The square root of 13221647 is about 3636.1582748830. The cubic root of 13221647 is about 236.4622690248.

Adding to 13221647 its reverse (74612231), we get a palindrome (87833878).

The spelling of 13221647 in words is "thirteen million, two hundred twenty-one thousand, six hundred forty-seven".