128271780 has 288 divisors, whose sum is σ = 493129728. Its totient is φ = 26265600.

The previous prime is 128271779. The next prime is 128271791. The reversal of 128271780 is 87172821.

It is a happy number.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 671485 + ... + 671675.

It is an arithmetic number, because the mean of its divisors is an integer number (1712256).

Almost surely, 2^128271780 is an apocalyptic number.

128271780 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 128271780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246564864).

128271780 is an abundant number, since it is smaller than the sum of its proper divisors (364857948).

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

128271780 is a wasteful number, since it uses less digits than its factorization.

128271780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267 (or 262 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 36.

The square root of 128271780 is about 11325.7132225746. The cubic root of 128271780 is about 504.3248567039.

The spelling of 128271780 in words is "one hundred twenty-eight million, two hundred seventy-one thousand, seven hundred eighty".