129139920 has 480 divisors, whose sum is σ = 561130752. Its totient is φ = 26873856.

The previous prime is 129139897. The next prime is 129139961. The reversal of 129139920 is 29931921.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nialpdrome in base 3.

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1769004 + ... + 1769076.

Almost surely, 2^129139920 is an apocalyptic number.

129139920 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 129139920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280565376).

129139920 is an abundant number, since it is smaller than the sum of its proper divisors (431990832).

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

129139920 is a wasteful number, since it uses less digits than its factorization.

129139920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 129139920 is about 11363.9746567827. The cubic root of 129139920 is about 505.4600519638.

The spelling of 129139920 in words is "one hundred twenty-nine million, one hundred thirty-nine thousand, nine hundred twenty".