12131111213 has 4 divisors (see below), whose sum is σ = 13064273628. Its totient is φ = 11197948800.

The previous prime is 12131111207. The next prime is 12131111221. The reversal of 12131111213 is 31211113121.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1066806244 + 11064304969 = 32662^2 + 105187^2 .

It is a cyclic number.

It is not a de Polignac number, because 12131111213 - 2¹⁶ = 12131045677 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12131111191 and 12131111200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12131111263) 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, 466581188 + ... + 466581213.

It is an arithmetic number, because the mean of its divisors is an integer number (3266068407).

Almost surely, 2^12131111213 is an apocalyptic number.

12131111213 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

12131111213 is a deficient number, since it is larger than the sum of its proper divisors (933162415).

12131111213 is an equidigital number, since it uses as much as digits as its factorization.

12131111213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 933162414.

The product of its digits is 36, while the sum is 17.

Adding to 12131111213 its reverse (31211113121), we get a palindrome (43342224334).

The spelling of 12131111213 in words is "twelve billion, one hundred thirty-one million, one hundred eleven thousand, two hundred thirteen".