133729681 has 2 divisors, whose sum is σ = 133729682. Its totient is φ = 133729680.

The previous prime is 133729663. The next prime is 133729697. The reversal of 133729681 is 186927331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121198081 + 12531600 = 11009^2 + 3540^2 .

It is an emirp because it is prime and its reverse (186927331) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 133729681 - 2⁷ = 133729553 is a prime.

It is a super-3 number, since 3×133729681³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (133729621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66864840 + 66864841.

It is an arithmetic number, because the mean of its divisors is an integer number (66864841).

Almost surely, 2^133729681 is an apocalyptic number.

It is an amenable number.

133729681 is a deficient number, since it is larger than the sum of its proper divisors (1).

133729681 is an equidigital number, since it uses as much as digits as its factorization.

133729681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 40.

The square root of 133729681 is about 11564.1550058792. The cubic root of 133729681 is about 511.3786624287.

The spelling of 133729681 in words is "one hundred thirty-three million, seven hundred twenty-nine thousand, six hundred eighty-one".