129999005 has 6 divisors (see below), whose sum is σ = 156029406. Its totient is φ = 103978808.

The previous prime is 129998989. The next prime is 129999011. The reversal of 129999005 is 500999921.

It can be written as a sum of positive squares in only one way, i.e., 103999204 + 25999801 = 10198^2 + 5099^2 .

It is not a de Polignac number, because 129999005 - 2⁴ = 129998989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 5 ways as a sum of consecutive naturals, for example, 22946 + ... + 28044.

It is an arithmetic number, because the mean of its divisors is an integer number (26004901).

Almost surely, 2^129999005 is an apocalyptic number.

It is an amenable number.

129999005 is a deficient number, since it is larger than the sum of its proper divisors (26030401).

129999005 is an frugal number, since it uses more digits than its factorization.

129999005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10203 (or 5104 counting only the distinct ones).

The product of its (nonzero) digits is 65610, while the sum is 44.

The square root of 129999005 is about 11401.7106172714. The cubic root of 129999005 is about 506.5784094791.

The spelling of 129999005 in words is "one hundred twenty-nine million, nine hundred ninety-nine thousand, five".