129185955 has 32 divisors (see below), whose sum is σ = 230310720. Its totient is φ = 68705280.

The previous prime is 129185951. The next prime is 129185977. The reversal of 129185955 is 559581921.

It is a Cunningham number, because it is equal to 11366²-1.

It is not a de Polignac number, because 129185955 - 2² = 129185951 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 129185955.

It is not an unprimeable number, because it can be changed into a prime (129185951) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 55699 + ... + 57971.

It is an arithmetic number, because the mean of its divisors is an integer number (7197210).

Almost surely, 2^129185955 is an apocalyptic number.

129185955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

129185955 is a deficient number, since it is larger than the sum of its proper divisors (101124765).

129185955 is a wasteful number, since it uses less digits than its factorization.

129185955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2708 (or 2702 counting only the distinct ones).

The product of its digits is 162000, while the sum is 45.

The square root of 129185955 is about 11365.9999560092. Note that the first 4 decimals coincide. The cubic root of 129185955 is about 505.5201059196.

The spelling of 129185955 in words is "one hundred twenty-nine million, one hundred eighty-five thousand, nine hundred fifty-five".