1320312121 has 4 divisors (see below), whose sum is σ = 1341956644. Its totient is φ = 1298667600.

The previous prime is 1320312113. The next prime is 1320312143. The reversal of 1320312121 is 1212130231.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 44036496 + 1276275625 = 6636^2 + 35725^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320312121 - 2³ = 1320312113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320312095 and 1320312104.

It is not an unprimeable number, because it can be changed into a prime (1320312101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10822170 + ... + 10822291.

It is an arithmetic number, because the mean of its divisors is an integer number (335489161).

Almost surely, 2^1320312121 is an apocalyptic number.

It is an amenable number.

1320312121 is a deficient number, since it is larger than the sum of its proper divisors (21644523).

1320312121 is an equidigital number, since it uses as much as digits as its factorization.

1320312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21644522.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1320312121 is about 36336.0994191727. The cubic root of 1320312121 is about 1097.0477644457.

Adding to 1320312121 its reverse (1212130231), we get a palindrome (2532442352).

The spelling of 1320312121 in words is "one billion, three hundred twenty million, three hundred twelve thousand, one hundred twenty-one".