1312113231221 has 8 divisors (see below), whose sum is σ = 1416568826904. Its totient is φ = 1208161036800.

The previous prime is 1312113231203. The next prime is 1312113231227. The reversal of 1312113231221 is 1221323112131.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 512492764996 + 799620466225 = 715886^2 + 894215^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1312113231221 - 2³⁸ = 1037235324277 is a prime.

It is a super-2 number, since 2×1312113231221² (a number of 25 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 (1312113231227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 125844896 + ... + 125855321.

It is an arithmetic number, because the mean of its divisors is an integer number (177071103363).

Almost surely, 2^{1312113231221} is an apocalyptic number.

It is an amenable number.

1312113231221 is a deficient number, since it is larger than the sum of its proper divisors (104455595683).

1312113231221 is a wasteful number, since it uses less digits than its factorization.

1312113231221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251700631.

The product of its digits is 432, while the sum is 23.

Adding to 1312113231221 its reverse (1221323112131), we get a palindrome (2533436343352).

The spelling of 1312113231221 in words is "one trillion, three hundred twelve billion, one hundred thirteen million, two hundred thirty-one thousand, two hundred twenty-one".