129992609 has 2 divisors, whose sum is σ = 129992610. Its totient is φ = 129992608.

The previous prime is 129992593. The next prime is 129992627. The reversal of 129992609 is 906299921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68840209 + 61152400 = 8297^2 + 7820^2 .

It is a cyclic number.

It is not a de Polignac number, because 129992609 - 2⁴ = 129992593 is a prime.

It is not a weakly prime, because it can be changed into another prime (129992809) 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, 64996304 + 64996305.

It is an arithmetic number, because the mean of its divisors is an integer number (64996305).

Almost surely, 2^129992609 is an apocalyptic number.

It is an amenable number.

129992609 is a deficient number, since it is larger than the sum of its proper divisors (1).

129992609 is an equidigital number, since it uses as much as digits as its factorization.

129992609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 129992609 is about 11401.4301295934. The cubic root of 129992609 is about 506.5701013933.

The spelling of 129992609 in words is "one hundred twenty-nine million, nine hundred ninety-two thousand, six hundred nine".