13656217 has 2 divisors, whose sum is σ = 13656218. Its totient is φ = 13656216.

The previous prime is 13656173. The next prime is 13656259. The reversal of 13656217 is 71265631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8886361 + 4769856 = 2981^2 + 2184^2 .

It is an emirp because it is prime and its reverse (71265631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13656217 - 2²³ = 5267609 is a prime.

It is not a weakly prime, because it can be changed into another prime (13656277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6828108 + 6828109.

It is an arithmetic number, because the mean of its divisors is an integer number (6828109).

Almost surely, 2^13656217 is an apocalyptic number.

It is an amenable number.

13656217 is a deficient number, since it is larger than the sum of its proper divisors (1).

13656217 is an equidigital number, since it uses as much as digits as its factorization.

13656217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7560, while the sum is 31.

The square root of 13656217 is about 3695.4319098043. The cubic root of 13656217 is about 239.0250786286.

The spelling of 13656217 in words is "thirteen million, six hundred fifty-six thousand, two hundred seventeen".