1312025521 has 4 divisors (see below), whose sum is σ = 1314896932. Its totient is φ = 1309154112.

The previous prime is 1312025509. The next prime is 1312025527. The reversal of 1312025521 is 1255202131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1255202131 = 5437 ⋅230863.

It can be written as a sum of positive squares in 2 ways, for example, as 1215219600 + 96805921 = 34860^2 + 9839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312025521 - 2⁵ = 1312025489 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1312025492 and 1312025501.

It is not an unprimeable number, because it can be changed into a prime (1312025527) 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, 1435020 + ... + 1435933.

It is an arithmetic number, because the mean of its divisors is an integer number (328724233).

Almost surely, 2^1312025521 is an apocalyptic number.

It is an amenable number.

1312025521 is a deficient number, since it is larger than the sum of its proper divisors (2871411).

1312025521 is an equidigital number, since it uses as much as digits as its factorization.

1312025521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2871410.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 1312025521 is about 36221.8928412086. The cubic root of 1312025521 is about 1094.7478332059.

Adding to 1312025521 its reverse (1255202131), we get a palindrome (2567227652).

The spelling of 1312025521 in words is "one billion, three hundred twelve million, twenty-five thousand, five hundred twenty-one".