129776172 has 12 divisors (see below), whose sum is σ = 302811096. Its totient is φ = 43258720.

The previous prime is 129776149. The next prime is 129776173. The reversal of 129776172 is 271677921.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (129776173) 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, 5407329 + ... + 5407352.

It is an arithmetic number, because the mean of its divisors is an integer number (25234258).

Almost surely, 2^129776172 is an apocalyptic number.

129776172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

129776172 is an abundant number, since it is smaller than the sum of its proper divisors (173034924).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129776172 is a wasteful number, since it uses less digits than its factorization.

129776172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10814688 (or 10814686 counting only the distinct ones).

The product of its digits is 74088, while the sum is 42.

The square root of 129776172 is about 11391.9345152612. The cubic root of 129776172 is about 506.2887997088.

The spelling of 129776172 in words is "one hundred twenty-nine million, seven hundred seventy-six thousand, one hundred seventy-two".