13121231231 has 4 divisors (see below), whose sum is σ = 13121465952. Its totient is φ = 13120996512.

The previous prime is 13121231141. The next prime is 13121231239. The reversal of 13121231231 is 13213212131.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 13121231231 - 2³⁰ = 12047489407 is a prime.

It is a super-2 number, since 2×13121231231² (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 (13121231239) 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, 20375 + ... + 163271.

It is an arithmetic number, because the mean of its divisors is an integer number (3280366488).

Almost surely, 2^13121231231 is an apocalyptic number.

13121231231 is a deficient number, since it is larger than the sum of its proper divisors (234721).

13121231231 is an equidigital number, since it uses as much as digits as its factorization.

13121231231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234720.

The product of its digits is 216, while the sum is 20.

Adding to 13121231231 its reverse (13213212131), we get a palindrome (26334443362).

The spelling of 13121231231 in words is "thirteen billion, one hundred twenty-one million, two hundred thirty-one thousand, two hundred thirty-one".