1312120813 has 4 divisors (see below), whose sum is σ = 1369169568. Its totient is φ = 1255072060.

The previous prime is 1312120801. The next prime is 1312120819. The reversal of 1312120813 is 3180212131.

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 1312120813 - 2¹⁷ = 1311989741 is a prime.

It is a super-2 number, since 2×1312120813² = 3443322055815561938, which 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 (1312120819) 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, 28524343 + ... + 28524388.

It is an arithmetic number, because the mean of its divisors is an integer number (342292392).

Almost surely, 2^1312120813 is an apocalyptic number.

It is an amenable number.

1312120813 is a deficient number, since it is larger than the sum of its proper divisors (57048755).

1312120813 is an equidigital number, since it uses as much as digits as its factorization.

1312120813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57048754.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 1312120813 is about 36223.2082096548. The cubic root of 1312120813 is about 1094.7743362943.

Adding to 1312120813 its reverse (3180212131), we get a palindrome (4492332944).

The spelling of 1312120813 in words is "one billion, three hundred twelve million, one hundred twenty thousand, eight hundred thirteen".