1312011321 has 4 divisors (see below), whose sum is σ = 1749348432. Its totient is φ = 874674212.

The previous prime is 1312011317. The next prime is 1312011341. The reversal of 1312011321 is 1231102131.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1312011321 - 2² = 1312011317 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1312011321.

It is not an unprimeable number, because it can be changed into a prime (1312011341) 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, 218668551 + ... + 218668556.

It is an arithmetic number, because the mean of its divisors is an integer number (437337108).

Almost surely, 2^1312011321 is an apocalyptic number.

It is an amenable number.

1312011321 is a deficient number, since it is larger than the sum of its proper divisors (437337111).

1312011321 is an equidigital number, since it uses as much as digits as its factorization.

1312011321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437337110.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1312011321 is about 36221.6968266259. The cubic root of 1312011321 is about 1094.7438837209.

Adding to 1312011321 its reverse (1231102131), we get a palindrome (2543113452).

The spelling of 1312011321 in words is "one billion, three hundred twelve million, eleven thousand, three hundred twenty-one".