128566780 has 48 divisors (see below), whose sum is σ = 283026240. Its totient is φ = 48964608.

The previous prime is 128566777. The next prime is 128566843. The reversal of 128566780 is 87665821.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 126916 + ... + 127924.

It is an arithmetic number, because the mean of its divisors is an integer number (5896380).

Almost surely, 2^128566780 is an apocalyptic number.

128566780 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 128566780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141513120).

128566780 is an abundant number, since it is smaller than the sum of its proper divisors (154459460).

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

128566780 is a wasteful number, since it uses less digits than its factorization.

128566780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318 (or 1316 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 128566780 is about 11338.7292056914. The cubic root of 128566780 is about 504.7111768710.

The spelling of 128566780 in words is "one hundred twenty-eight million, five hundred sixty-six thousand, seven hundred eighty".