131323212121 has 4 divisors (see below), whose sum is σ = 131344159744. Its totient is φ = 131302264500.

The previous prime is 131323212109. The next prime is 131323212149. The reversal of 131323212121 is 121212323131.

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: 121212323131 = 38611 ⋅3139321.

It is a cyclic number.

It is not a de Polignac number, because 131323212121 - 2⁷ = 131323211993 is a prime.

It is a super-2 number, since 2×131323212121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131323212092 and 131323212101.

It is not an unprimeable number, because it can be changed into a prime (131323212521) 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, 10464405 + ... + 10476946.

It is an arithmetic number, because the mean of its divisors is an integer number (32836039936).

Almost surely, 2^131323212121 is an apocalyptic number.

It is an amenable number.

131323212121 is a deficient number, since it is larger than the sum of its proper divisors (20947623).

131323212121 is an equidigital number, since it uses as much as digits as its factorization.

131323212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20947622.

The product of its digits is 432, while the sum is 22.

Adding to 131323212121 its reverse (121212323131), we get a palindrome (252535535252).

The spelling of 131323212121 in words is "one hundred thirty-one billion, three hundred twenty-three million, two hundred twelve thousand, one hundred twenty-one".