128525820 has 24 divisors (see below), whose sum is σ = 359872464. Its totient is φ = 34273536.

The previous prime is 128525809. The next prime is 128525821. The reversal of 128525820 is 28525821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128525821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1070989 + ... + 1071108.

It is an arithmetic number, because the mean of its divisors is an integer number (14994686).

Almost surely, 2^128525820 is an apocalyptic number.

128525820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128525820 is an abundant number, since it is smaller than the sum of its proper divisors (231346644).

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

128525820 is a wasteful number, since it uses less digits than its factorization.

128525820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2142109 (or 2142107 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 33.

The square root of 128525820 is about 11336.9228629289. The cubic root of 128525820 is about 504.6575726518.

Subtracting from 128525820 its reverse (28525821), we obtain a palindrome (99999999).

The spelling of 128525820 in words is "one hundred twenty-eight million, five hundred twenty-five thousand, eight hundred twenty".