13218613 has 4 divisors (see below), whose sum is σ = 13292640. Its totient is φ = 13144588.

The previous prime is 13218607. The next prime is 13218619. The reversal of 13218613 is 31681231.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (13218607) and next prime (13218619).

It is a cyclic number.

It is not a de Polignac number, because 13218613 - 2⁵ = 13218581 is a prime.

It is a super-3 number, since 3×13218613³ (a number of 22 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13218619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36745 + ... + 37102.

It is an arithmetic number, because the mean of its divisors is an integer number (3323160).

Almost surely, 2^13218613 is an apocalyptic number.

It is an amenable number.

13218613 is a deficient number, since it is larger than the sum of its proper divisors (74027).

13218613 is an equidigital number, since it uses as much as digits as its factorization.

13218613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74026.

The product of its digits is 864, while the sum is 25.

The square root of 13218613 is about 3635.7410523853. The cubic root of 13218613 is about 236.4441804713. Note that the first 3 decimals are identical.

Adding to 13218613 its reverse (31681231), we get a palindrome (44899844).

It can be divided in two parts, 13218 and 613, that added together give a palindrome (13831).

The spelling of 13218613 in words is "thirteen million, two hundred eighteen thousand, six hundred thirteen".