128218666 has 8 divisors (see below), whose sum is σ = 198532224. Its totient is φ = 62041260.

The previous prime is 128218663. The next prime is 128218681. The reversal of 128218666 is 666812821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (128218663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1033960 + ... + 1034083.

It is an arithmetic number, because the mean of its divisors is an integer number (24816528).

Almost surely, 2^128218666 is an apocalyptic number.

128218666 is a deficient number, since it is larger than the sum of its proper divisors (70313558).

128218666 is a wasteful number, since it uses less digits than its factorization.

128218666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2068076.

The product of its digits is 55296, while the sum is 40.

The square root of 128218666 is about 11323.3681385001. The cubic root of 128218666 is about 504.2552378355.

The spelling of 128218666 in words is "one hundred twenty-eight million, two hundred eighteen thousand, six hundred sixty-six".