129205120 has 64 divisors (see below), whose sum is σ = 336979440. Its totient is φ = 46981120.

The previous prime is 129205091. The next prime is 129205123. The reversal of 129205120 is 21502921.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-3 number, since 3×129205120³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 129205091 and 129205100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129205123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2137 + ... + 16216.

Almost surely, 2^129205120 is an apocalyptic number.

129205120 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 129205120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168489720).

129205120 is an abundant number, since it is smaller than the sum of its proper divisors (207774320).

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

129205120 is a wasteful number, since it uses less digits than its factorization.

129205120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18383 (or 18371 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 129205120 is about 11366.8430093848. The cubic root of 129205120 is about 505.5451029965.

The spelling of 129205120 in words is "one hundred twenty-nine million, two hundred five thousand, one hundred twenty".