128869666 has 16 divisors (see below), whose sum is σ = 210044160. Its totient is φ = 59073840.

The previous prime is 128869651. The next prime is 128869669. The reversal of 128869666 is 666968821.

It is not an unprimeable number, because it can be changed into a prime (128869669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53521 + ... + 55876.

It is an arithmetic number, because the mean of its divisors is an integer number (13127760).

Almost surely, 2^128869666 is an apocalyptic number.

128869666 is a deficient number, since it is larger than the sum of its proper divisors (81174494).

128869666 is a wasteful number, since it uses less digits than its factorization.

128869666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109449.

The product of its digits is 1492992, while the sum is 52.

The square root of 128869666 is about 11352.0776072048. The cubic root of 128869666 is about 505.1072098623.

The spelling of 128869666 in words is "one hundred twenty-eight million, eight hundred sixty-nine thousand, six hundred sixty-six".