13653221 has 2 divisors, whose sum is σ = 13653222. Its totient is φ = 13653220.

The previous prime is 13653197. The next prime is 13653239. The reversal of 13653221 is 12235631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13653025 + 196 = 3695^2 + 14^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13653221 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 (13673221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6826610 + 6826611.

It is an arithmetic number, because the mean of its divisors is an integer number (6826611).

Almost surely, 2^13653221 is an apocalyptic number.

It is an amenable number.

13653221 is a deficient number, since it is larger than the sum of its proper divisors (1).

13653221 is an equidigital number, since it uses as much as digits as its factorization.

13653221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 23.

The square root of 13653221 is about 3695.0265222323. The cubic root of 13653221 is about 239.0075976647.

Adding to 13653221 its reverse (12235631), we get a palindrome (25888852).

The spelling of 13653221 in words is "thirteen million, six hundred fifty-three thousand, two hundred twenty-one".