128129280 has 144 divisors (see below), whose sum is σ = 416681664. Its totient is φ = 33546240.

The previous prime is 128129269. The next prime is 128129291. The reversal of 128129280 is 82921821.

It is an interprime number because it is at equal distance from previous prime (128129269) and next prime (128129291).

It is a super-2 number, since 2×128129280² = 32834224786636800, which contains 22 as substring.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 233967 + ... + 234513.

Almost surely, 2^128129280 is an apocalyptic number.

128129280 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 128129280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208340832).

128129280 is an abundant number, since it is smaller than the sum of its proper divisors (288552384).

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

128129280 is an equidigital number, since it uses as much as digits as its factorization.

128129280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 33.

The square root of 128129280 is about 11319.4204798656. The cubic root of 128129280 is about 504.1380322360.

The spelling of 128129280 in words is "one hundred twenty-eight million, one hundred twenty-nine thousand, two hundred eighty".