1321131311 has 4 divisors (see below), whose sum is σ = 1324673592. Its totient is φ = 1317589032.

The previous prime is 1321131283. The next prime is 1321131359. The reversal of 1321131311 is 1131311231.

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 1321131311 - 2³⁰ = 247389487 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1321131311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321131211) 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, 1770581 + ... + 1771326.

It is an arithmetic number, because the mean of its divisors is an integer number (331168398).

Almost surely, 2^1321131311 is an apocalyptic number.

1321131311 is a deficient number, since it is larger than the sum of its proper divisors (3542281).

1321131311 is an equidigital number, since it uses as much as digits as its factorization.

1321131311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3542280.

The product of its digits is 54, while the sum is 17.

The square root of 1321131311 is about 36347.3700699239. The cubic root of 1321131311 is about 1097.2746059486.

Adding to 1321131311 its reverse (1131311231), we get a palindrome (2452442542).

The spelling of 1321131311 in words is "one billion, three hundred twenty-one million, one hundred thirty-one thousand, three hundred eleven".