129000999 has 4 divisors (see below), whose sum is σ = 172001336. Its totient is φ = 86000664.

The previous prime is 129000983. The next prime is 129001021. The reversal of 129000999 is 999000921.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 129000999 - 2⁴ = 129000983 is a prime.

It is a Duffinian number.

129000999 is a modest number, since divided by 999 gives 129 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129000499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21500164 + ... + 21500169.

It is an arithmetic number, because the mean of its divisors is an integer number (43000334).

Almost surely, 2^129000999 is an apocalyptic number.

129000999 is a deficient number, since it is larger than the sum of its proper divisors (43000337).

129000999 is an equidigital number, since it uses as much as digits as its factorization.

129000999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43000336.

The product of its (nonzero) digits is 13122, while the sum is 39.

The square root of 129000999 is about 11357.8606700382. The cubic root of 129000999 is about 505.2787390383.

The spelling of 129000999 in words is "one hundred twenty-nine million, nine hundred ninety-nine", and thus it is an aban number.