128611872 has 36 divisors (see below), whose sum is σ = 365740830. Its totient is φ = 42870528.

The previous prime is 128611843. The next prime is 128611907. The reversal of 128611872 is 278116821.

It can be written as a sum of positive squares in only one way, i.e., 122677776 + 5934096 = 11076^2 + 2436^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222997 + ... + 223572.

Almost surely, 2^128611872 is an apocalyptic number.

128611872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

128611872 is an abundant number, since it is smaller than the sum of its proper divisors (237128958).

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

128611872 is a wasteful number, since it uses less digits than its factorization.

128611872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446585 (or 446574 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

The square root of 128611872 is about 11340.7174376227. The cubic root of 128611872 is about 504.7701754611.

The spelling of 128611872 in words is "one hundred twenty-eight million, six hundred eleven thousand, eight hundred seventy-two".