128725820 has 12 divisors (see below), whose sum is σ = 270324264. Its totient is φ = 51490320.

The previous prime is 128725811. The next prime is 128725823. The reversal of 128725820 is 28527821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128725823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3218126 + ... + 3218165.

It is an arithmetic number, because the mean of its divisors is an integer number (22527022).

Almost surely, 2^128725820 is an apocalyptic number.

128725820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128725820 is an abundant number, since it is smaller than the sum of its proper divisors (141598444).

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

128725820 is a wasteful number, since it uses less digits than its factorization.

128725820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6436300 (or 6436298 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 128725820 is about 11345.7401697730. The cubic root of 128725820 is about 504.9192041442.

The spelling of 128725820 in words is "one hundred twenty-eight million, seven hundred twenty-five thousand, eight hundred twenty".