133716817681 has 2 divisors, whose sum is σ = 133716817682. Its totient is φ = 133716817680.

The previous prime is 133716817667. The next prime is 133716817691. The reversal of 133716817681 is 186718617331.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131775534081 + 1941283600 = 363009^2 + 44060^2 .

It is a cyclic number.

It is not a de Polignac number, because 133716817681 - 2⁵ = 133716817649 is a prime.

It is a super-2 number, since 2×133716817681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (133716817691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66858408840 + 66858408841.

It is an arithmetic number, because the mean of its divisors is an integer number (66858408841).

Almost surely, 2^133716817681 is an apocalyptic number.

It is an amenable number.

133716817681 is a deficient number, since it is larger than the sum of its proper divisors (1).

133716817681 is an equidigital number, since it uses as much as digits as its factorization.

133716817681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1016064, while the sum is 52.

The spelling of 133716817681 in words is "one hundred thirty-three billion, seven hundred sixteen million, eight hundred seventeen thousand, six hundred eighty-one".