13321661537 has 2 divisors, whose sum is σ = 13321661538. Its totient is φ = 13321661536.

The previous prime is 13321661513. The next prime is 13321661579. The reversal of 13321661537 is 73516612331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12872263936 + 449397601 = 113456^2 + 21199^2 .

It is a cyclic number.

It is not a de Polignac number, because 13321661537 - 2⁸ = 13321661281 is a prime.

It is a super-2 number, since 2×13321661537² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 13321661537.

It is not a weakly prime, because it can be changed into another prime (13321661597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6660830768 + 6660830769.

It is an arithmetic number, because the mean of its divisors is an integer number (6660830769).

Almost surely, 2^13321661537 is an apocalyptic number.

It is an amenable number.

13321661537 is a deficient number, since it is larger than the sum of its proper divisors (1).

13321661537 is an equidigital number, since it uses as much as digits as its factorization.

13321661537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 68040, while the sum is 38.

The spelling of 13321661537 in words is "thirteen billion, three hundred twenty-one million, six hundred sixty-one thousand, five hundred thirty-seven".