128500657280 has 32 divisors (see below), whose sum is σ = 307196885340. Its totient is φ = 51400262656.

The previous prime is 128500657279. The next prime is 128500657289. The reversal of 128500657280 is 82756005821.

It can be written as a sum of positive squares in 2 ways, for example, as 126229562944 + 2271094336 = 355288^2 + 47656^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (128500657289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100390499 + ... + 100391778.

Almost surely, 2^128500657280 is an apocalyptic number.

128500657280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128500657280 is an abundant number, since it is smaller than the sum of its proper divisors (178696228060).

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

128500657280 is an equidigital number, since it uses as much as digits as its factorization.

128500657280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200782296 (or 200782284 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 44.

The spelling of 128500657280 in words is "one hundred twenty-eight billion, five hundred million, six hundred fifty-seven thousand, two hundred eighty".