13815213 has 4 divisors (see below), whose sum is σ = 18420288. Its totient is φ = 9210140.

The previous prime is 13815209. The next prime is 13815229. The reversal of 13815213 is 31251831.

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 a cyclic number.

It is not a de Polignac number, because 13815213 - 2² = 13815209 is a prime.

It is a super-2 number, since 2×13815213² = 381720220470738, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13815233) 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, 2302533 + ... + 2302538.

It is an arithmetic number, because the mean of its divisors is an integer number (4605072).

Almost surely, 2^13815213 is an apocalyptic number.

It is an amenable number.

13815213 is a deficient number, since it is larger than the sum of its proper divisors (4605075).

13815213 is an equidigital number, since it uses as much as digits as its factorization.

13815213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4605074.

The product of its digits is 720, while the sum is 24.

The square root of 13815213 is about 3716.8821611668. The cubic root of 13815213 is about 239.9491385276.

It can be divided in two parts, 13815 and 213, that added together give a triangular number (14028 = T₁₆₇).

The spelling of 13815213 in words is "thirteen million, eight hundred fifteen thousand, two hundred thirteen".