1311433121 has 4 divisors (see below), whose sum is σ = 1315570452. Its totient is φ = 1307295792.

The previous prime is 1311433111. The next prime is 1311433127. The reversal of 1311433121 is 1213341131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1213341131 = 353 ⋅3437227.

It can be written as a sum of positive squares in 2 ways, for example, as 502656400 + 808776721 = 22420^2 + 28439^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311433121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1311433093 and 1311433102.

It is not an unprimeable number, because it can be changed into a prime (1311433127) 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, 2068190 + ... + 2068823.

It is an arithmetic number, because the mean of its divisors is an integer number (328892613).

Almost surely, 2^1311433121 is an apocalyptic number.

It is an amenable number.

1311433121 is a deficient number, since it is larger than the sum of its proper divisors (4137331).

1311433121 is an equidigital number, since it uses as much as digits as its factorization.

1311433121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4137330.

The product of its digits is 216, while the sum is 20.

The square root of 1311433121 is about 36213.7145429739. The cubic root of 1311433121 is about 1094.5830431574.

Adding to 1311433121 its reverse (1213341131), we get a palindrome (2524774252).

The spelling of 1311433121 in words is "one billion, three hundred eleven million, four hundred thirty-three thousand, one hundred twenty-one".