128129520 has 160 divisors (see below), whose sum is σ = 417973248. Its totient is φ = 32431104.

The previous prime is 128129513. The next prime is 128129579. The reversal of 128129520 is 25921821.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 417207 + ... + 417513.

Almost surely, 2^128129520 is an apocalyptic number.

128129520 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 128129520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208986624).

128129520 is an abundant number, since it is smaller than the sum of its proper divisors (289843728).

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

128129520 is a wasteful number, since it uses less digits than its factorization.

128129520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 30.

The square root of 128129520 is about 11319.4310811100. The cubic root of 128129520 is about 504.1383470042.

The spelling of 128129520 in words is "one hundred twenty-eight million, one hundred twenty-nine thousand, five hundred twenty".