129000055 has 16 divisors (see below), whose sum is σ = 158436288. Its totient is φ = 100800000.

The previous prime is 129000049. The next prime is 129000103. The reversal of 129000055 is 550000921.

It is not a de Polignac number, because 129000055 - 2¹⁷ = 128868983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44655 + ... + 47455.

It is an arithmetic number, because the mean of its divisors is an integer number (9902268).

Almost surely, 2^129000055 is an apocalyptic number.

129000055 is a deficient number, since it is larger than the sum of its proper divisors (29436233).

129000055 is a wasteful number, since it uses less digits than its factorization.

129000055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3018.

The product of its (nonzero) digits is 450, while the sum is 22.

The square root of 129000055 is about 11357.8191128403. The cubic root of 129000055 is about 505.2775065303.

Adding to 129000055 its reverse (550000921), we get a palindrome (679000976).

The spelling of 129000055 in words is "one hundred twenty-nine million, fifty-five", and thus it is an aban number.