13218081231 has 4 divisors (see below), whose sum is σ = 17624108312. Its totient is φ = 8812054152.

The previous prime is 13218081199. The next prime is 13218081257.

13218081231 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 13218081231 - 2⁵ = 13218081199 is a prime.

It is a super-2 number, since 2×13218081231² (a number of 21 digits) contains 22 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 (13218081271) 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, 2203013536 + ... + 2203013541.

It is an arithmetic number, because the mean of its divisors is an integer number (4406027078).

Almost surely, 2^13218081231 is an apocalyptic number.

13218081231 is a deficient number, since it is larger than the sum of its proper divisors (4406027081).

13218081231 is an equidigital number, since it uses as much as digits as its factorization.

13218081231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4406027080.

The product of its (nonzero) digits is 2304, while the sum is 30.

The spelling of 13218081231 in words is "thirteen billion, two hundred eighteen million, eighty-one thousand, two hundred thirty-one".