129209850 has 288 divisors, whose sum is σ = 451221120. Its totient is φ = 26611200.

The previous prime is 129209849. The next prime is 129209869. The reversal of 129209850 is 58902921.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1143394 + ... + 1143506.

It is an arithmetic number, because the mean of its divisors is an integer number (1566740).

Almost surely, 2^129209850 is an apocalyptic number.

129209850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 129209850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225610560).

129209850 is an abundant number, since it is smaller than the sum of its proper divisors (322011270).

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

129209850 is a wasteful number, since it uses less digits than its factorization.

129209850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 141 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 129209850 is about 11367.0510687689. The cubic root of 129209850 is about 505.5512719965.

The spelling of 129209850 in words is "one hundred twenty-nine million, two hundred nine thousand, eight hundred fifty".