1321131331 has 4 divisors (see below), whose sum is σ = 1422756832. Its totient is φ = 1219505832.

The previous prime is 1321131283. The next prime is 1321131359. The reversal of 1321131331 is 1331311231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1331311231 = 23 ⋅57883097.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321131331 is a prime.

It is a super-2 number, since 2×1321131331² = 3490775987499663122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321131299 and 1321131308.

It is not an unprimeable number, because it can be changed into a prime (1321131631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50812731 + ... + 50812756.

It is an arithmetic number, because the mean of its divisors is an integer number (355689208).

Almost surely, 2^1321131331 is an apocalyptic number.

1321131331 is a deficient number, since it is larger than the sum of its proper divisors (101625501).

1321131331 is a wasteful number, since it uses less digits than its factorization.

1321131331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101625500.

The product of its digits is 162, while the sum is 19.

The square root of 1321131331 is about 36347.3703450470. The cubic root of 1321131331 is about 1097.2746114857.

Adding to 1321131331 its reverse (1331311231), we get a palindrome (2652442562).

The spelling of 1321131331 in words is "one billion, three hundred twenty-one million, one hundred thirty-one thousand, three hundred thirty-one".