128205431564 has 12 divisors (see below), whose sum is σ = 256410863184. Its totient is φ = 54945184944.

The previous prime is 128205431537. The next prime is 128205431587. The reversal of 128205431564 is 465134502821.

128205431564 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

128205431564 is an admirable number.

It is a super-2 number, since 2×128205431564² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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, 2289382679 + ... + 2289382734.

It is an arithmetic number, because the mean of its divisors is an integer number (21367571932).

Almost surely, 2^128205431564 is an apocalyptic number.

128205431564 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

128205431564 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

128205431564 is a wasteful number, since it uses less digits than its factorization.

128205431564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4578765424 (or 4578765422 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 41.

The spelling of 128205431564 in words is "one hundred twenty-eight billion, two hundred five million, four hundred thirty-one thousand, five hundred sixty-four".