128105866 has 32 divisors (see below), whose sum is σ = 231937920. Its totient is φ = 51840000.

The previous prime is 128105819. The next prime is 128105899. The reversal of 128105866 is 668501821.

It is a super-2 number, since 2×128105866² = 32822225807219912, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106066 + ... + 107266.

It is an arithmetic number, because the mean of its divisors is an integer number (7248060).

Almost surely, 2^128105866 is an apocalyptic number.

128105866 is a deficient number, since it is larger than the sum of its proper divisors (103832054).

128105866 is a wasteful number, since it uses less digits than its factorization.

128105866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1630.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 128105866 is about 11318.3861923863. The cubic root of 128105866 is about 504.1073220893.

The spelling of 128105866 in words is "one hundred twenty-eight million, one hundred five thousand, eight hundred sixty-six".