129491723 has 2 divisors, whose sum is σ = 129491724. Its totient is φ = 129491722.

The previous prime is 129491701. The next prime is 129491731. The reversal of 129491723 is 327194921.

It is a strong prime.

It is an emirp because it is prime and its reverse (327194921) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129491723 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (129497723) 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, 64745861 + 64745862.

It is an arithmetic number, because the mean of its divisors is an integer number (64745862).

Almost surely, 2^129491723 is an apocalyptic number.

129491723 is a deficient number, since it is larger than the sum of its proper divisors (1).

129491723 is an equidigital number, since it uses as much as digits as its factorization.

129491723 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 38.

The square root of 129491723 is about 11379.4430004284. The cubic root of 129491723 is about 505.9186272621.

The spelling of 129491723 in words is "one hundred twenty-nine million, four hundred ninety-one thousand, seven hundred twenty-three".