13539661 has 2 divisors, whose sum is σ = 13539662. Its totient is φ = 13539660.

The previous prime is 13539641. The next prime is 13539671. The reversal of 13539661 is 16693531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9418761 + 4120900 = 3069^2 + 2030^2 .

It is a cyclic number.

It is not a de Polignac number, because 13539661 - 2¹⁵ = 13506893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13539601) 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, 6769830 + 6769831.

It is an arithmetic number, because the mean of its divisors is an integer number (6769831).

Almost surely, 2^13539661 is an apocalyptic number.

It is an amenable number.

13539661 is a deficient number, since it is larger than the sum of its proper divisors (1).

13539661 is an equidigital number, since it uses as much as digits as its factorization.

13539661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14580, while the sum is 34.

The square root of 13539661 is about 3679.6278344420. The cubic root of 13539661 is about 238.3431072763.

The spelling of 13539661 in words is "thirteen million, five hundred thirty-nine thousand, six hundred sixty-one".