128971818 has 32 divisors (see below), whose sum is σ = 288520320. Its totient is φ = 42703200.

The previous prime is 128971793. The next prime is 128971819. The reversal of 128971818 is 818179821.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (128971819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 246 + ... + 16062.

It is an arithmetic number, because the mean of its divisors is an integer number (9016260).

Almost surely, 2^128971818 is an apocalyptic number.

128971818 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

128971818 is an abundant number, since it is smaller than the sum of its proper divisors (159548502).

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

128971818 is a wasteful number, since it uses less digits than its factorization.

128971818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15979 (or 15973 counting only the distinct ones).

The product of its digits is 64512, while the sum is 45.

The square root of 128971818 is about 11356.5759804617. The cubic root of 128971818 is about 505.2406368765.

The spelling of 128971818 in words is "one hundred twenty-eight million, nine hundred seventy-one thousand, eight hundred eighteen".