13451221 has 12 divisors (see below), whose sum is σ = 16227552. Its totient is φ = 10920744.

The previous prime is 13451219. The next prime is 13451237. The reversal of 13451221 is 12215431.

It is not a de Polignac number, because 13451221 - 2¹ = 13451219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13451201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135 + ... + 5188.

It is an arithmetic number, because the mean of its divisors is an integer number (1352296).

Almost surely, 2^13451221 is an apocalyptic number.

It is an amenable number.

13451221 is a deficient number, since it is larger than the sum of its proper divisors (2776331).

13451221 is an equidigital number, since it uses as much as digits as its factorization.

13451221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5368 (or 5349 counting only the distinct ones).

The product of its digits is 240, while the sum is 19.

The square root of 13451221 is about 3667.5906260105. The cubic root of 13451221 is about 237.8230271137.

Adding to 13451221 its reverse (12215431), we get a palindrome (25666652).

The spelling of 13451221 in words is "thirteen million, four hundred fifty-one thousand, two hundred twenty-one".