1331513231 has 2 divisors, whose sum is σ = 1331513232. Its totient is φ = 1331513230.

The previous prime is 1331513173. The next prime is 1331513233. The reversal of 1331513231 is 1323151331.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1331513231 - 2⁶ = 1331513167 is a prime.

It is a super-2 number, since 2×1331513231² = 3545854968656118722, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 1331513233, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1331513197 and 1331513206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331513233) 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 as a sum of consecutive naturals, namely, 665756615 + 665756616.

It is an arithmetic number, because the mean of its divisors is an integer number (665756616).

Almost surely, 2^1331513231 is an apocalyptic number.

1331513231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331513231 is an equidigital number, since it uses as much as digits as its factorization.

1331513231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 810, while the sum is 23.

The square root of 1331513231 is about 36489.9058782014. The cubic root of 1331513231 is about 1100.1413677816.

Adding to 1331513231 its reverse (1323151331), we get a palindrome (2654664562).

The spelling of 1331513231 in words is "one billion, three hundred thirty-one million, five hundred thirteen thousand, two hundred thirty-one".