1312120015 has 4 divisors (see below), whose sum is σ = 1574544024. Its totient is φ = 1049696008.

The previous prime is 1312120013. The next prime is 1312120021. The reversal of 1312120015 is 5100212131.

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 1312120015 - 2¹ = 1312120013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312120013) 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, 131211997 + ... + 131212006.

It is an arithmetic number, because the mean of its divisors is an integer number (393636006).

Almost surely, 2^1312120015 is an apocalyptic number.

1312120015 is a deficient number, since it is larger than the sum of its proper divisors (262424009).

1312120015 is an equidigital number, since it uses as much as digits as its factorization.

1312120015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262424008.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 1312120015 is about 36223.1971946155. The cubic root of 1312120015 is about 1094.7741143559.

Adding to 1312120015 its reverse (5100212131), we get a palindrome (6412332146).

The spelling of 1312120015 in words is "one billion, three hundred twelve million, one hundred twenty thousand, fifteen".