128220857100 has 108 divisors (see below), whose sum is σ = 459315626224. Its totient is φ = 29307623040.

The previous prime is 128220857029. The next prime is 128220857101. The reversal of 128220857100 is 1758022821.

128220857100 is a `hidden beast` number, since 1 + 2 + 82 + 2 + 0 + 8 + 571 + 0 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (128220857101) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10169959 + ... + 10182558.

Almost surely, 2^128220857100 is an apocalyptic number.

128220857100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128220857100 is an abundant number, since it is smaller than the sum of its proper divisors (331094769124).

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

128220857100 is a wasteful number, since it uses less digits than its factorization.

128220857100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20352544 (or 20352534 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 36.

Adding to 128220857100 its reverse (1758022821), we get a palindrome (129978879921).

The spelling of 128220857100 in words is "one hundred twenty-eight billion, two hundred twenty million, eight hundred fifty-seven thousand, one hundred".