13556813 has 4 divisors (see below), whose sum is σ = 13601280. Its totient is φ = 13512348.

The previous prime is 13556783. The next prime is 13556831. The reversal of 13556813 is 31865531.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31865531 = 17 ⋅1874443.

It is a cyclic number.

It is not a de Polignac number, because 13556813 - 2¹⁸ = 13294669 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13556813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13552813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21773 + ... + 22386.

It is an arithmetic number, because the mean of its divisors is an integer number (3400320).

Almost surely, 2^13556813 is an apocalyptic number.

It is an amenable number.

13556813 is a deficient number, since it is larger than the sum of its proper divisors (44467).

13556813 is an equidigital number, since it uses as much as digits as its factorization.

13556813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44466.

The product of its digits is 10800, while the sum is 32.

The square root of 13556813 is about 3681.9577672754. The cubic root of 13556813 is about 238.4437089073.

The spelling of 13556813 in words is "thirteen million, five hundred fifty-six thousand, eight hundred thirteen".