18115113213 has 24 divisors (see below), whose sum is σ = 27179600448. Its totient is φ = 12057069024.

The previous prime is 18115113199. The next prime is 18115113239. The reversal of 18115113213 is 31231151181.

It is not a de Polignac number, because 18115113213 - 2⁴ = 18115113197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18115113253) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89520 + ... + 210342.

It is an arithmetic number, because the mean of its divisors is an integer number (1132483352).

Almost surely, 2^18115113213 is an apocalyptic number.

It is an amenable number.

18115113213 is a deficient number, since it is larger than the sum of its proper divisors (9064487235).

18115113213 is an equidigital number, since it uses as much as digits as its factorization.

18115113213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121455 (or 121443 counting only the distinct ones).

The product of its digits is 720, while the sum is 27.

Adding to 18115113213 its reverse (31231151181), we get a palindrome (49346264394).

It can be divided in two parts, 18115 and 113213, that added together give a triangular number (131328 = T₅₁₂).

The spelling of 18115113213 in words is "eighteen billion, one hundred fifteen million, one hundred thirteen thousand, two hundred thirteen".