129199969 has 2 divisors, whose sum is σ = 129199970. Its totient is φ = 129199968.

The previous prime is 129199951. The next prime is 129200009. The reversal of 129199969 is 969991921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128527569 + 672400 = 11337^2 + 820^2 .

It is a cyclic number.

It is not a de Polignac number, because 129199969 - 2⁵ = 129199937 is a prime.

It is a super-2 number, since 2×129199969² = 33385263979201922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (129193969) 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, 64599984 + 64599985.

It is an arithmetic number, because the mean of its divisors is an integer number (64599985).

Almost surely, 2^129199969 is an apocalyptic number.

It is an amenable number.

129199969 is a deficient number, since it is larger than the sum of its proper divisors (1).

129199969 is an equidigital number, since it uses as much as digits as its factorization.

129199969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 708588, while the sum is 55.

The square root of 129199969 is about 11366.6164270639. The cubic root of 129199969 is about 505.5383847451.

The spelling of 129199969 in words is "one hundred twenty-nine million, one hundred ninety-nine thousand, nine hundred sixty-nine".