13121231312 has 80 divisors (see below), whose sum is σ = 31513732992. Its totient is φ = 5163479040.

The previous prime is 13121231303. The next prime is 13121231323. The reversal of 13121231312 is 21313212131.

It is a happy number.

It is a super-2 number, since 2×13121231312² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5978 + ... + 162105.

Almost surely, 2^13121231312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13121231312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15756866496).

13121231312 is an abundant number, since it is smaller than the sum of its proper divisors (18392501680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13121231312 is a wasteful number, since it uses less digits than its factorization.

13121231312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168156 (or 168150 counting only the distinct ones).

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

Adding to 13121231312 its reverse (21313212131), we get a palindrome (34434443443).

The spelling of 13121231312 in words is "thirteen billion, one hundred twenty-one million, two hundred thirty-one thousand, three hundred twelve".