129521100 has 144 divisors (see below), whose sum is σ = 407751680. Its totient is φ = 31622400.

The previous prime is 129521099. The next prime is 129521123. The reversal of 129521100 is 1125921.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 176334 + ... + 177066.

Almost surely, 2^129521100 is an apocalyptic number.

129521100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129521100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203875840).

129521100 is an abundant number, since it is smaller than the sum of its proper divisors (278230580).

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

129521100 is a wasteful number, since it uses less digits than its factorization.

129521100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800 (or 793 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 21.

The square root of 129521100 is about 11380.7337197564. The cubic root of 129521100 is about 505.9568825972.

The spelling of 129521100 in words is "one hundred twenty-nine million, five hundred twenty-one thousand, one hundred".