129100880 has 20 divisors (see below), whose sum is σ = 300159732. Its totient is φ = 51640320.

The previous prime is 129100879. The next prime is 129100883. The reversal of 129100880 is 88001921.

It can be written as a sum of positive squares in 2 ways, for example, as 38241856 + 90859024 = 6184^2 + 9532^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129100883) 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, 806801 + ... + 806960.

Almost surely, 2^129100880 is an apocalyptic number.

129100880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129100880 is an abundant number, since it is smaller than the sum of its proper divisors (171058852).

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

129100880 is a wasteful number, since it uses less digits than its factorization.

129100880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1613774 (or 1613768 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 129100880 is about 11362.2568180798. The cubic root of 129100880 is about 505.4091119982.

The spelling of 129100880 in words is "one hundred twenty-nine million, one hundred thousand, eight hundred eighty".