1331533613 has 4 divisors (see below), whose sum is σ = 1335788028. Its totient is φ = 1327279200.

The previous prime is 1331533537. The next prime is 1331533627. The reversal of 1331533613 is 3163351331.

It is a happy number.

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 93760489 + 1237773124 = 9683^2 + 35182^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1331533613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331532613) 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, 2126738 + ... + 2127363.

It is an arithmetic number, because the mean of its divisors is an integer number (333947007).

Almost surely, 2^1331533613 is an apocalyptic number.

It is an amenable number.

1331533613 is a deficient number, since it is larger than the sum of its proper divisors (4254415).

1331533613 is an equidigital number, since it uses as much as digits as its factorization.

1331533613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4254414.

The product of its digits is 7290, while the sum is 29.

The square root of 1331533613 is about 36490.1851598481. The cubic root of 1331533613 is about 1100.1469811861.

Adding to 1331533613 its reverse (3163351331), we get a palindrome (4494884944).

The spelling of 1331533613 in words is "one billion, three hundred thirty-one million, five hundred thirty-three thousand, six hundred thirteen".