128358666 has 12 divisors (see below), whose sum is σ = 278110482. Its totient is φ = 42786216.

The previous prime is 128358589. The next prime is 128358673. The reversal of 128358666 is 666853821.

It can be written as a sum of positive squares in only one way, i.e., 128255625 + 103041 = 11325^2 + 321^2 .

It is a Curzon number.

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, 3565501 + ... + 3565536.

Almost surely, 2^128358666 is an apocalyptic number.

128358666 is an abundant number, since it is smaller than the sum of its proper divisors (149751816).

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

128358666 is a wasteful number, since it uses less digits than its factorization.

128358666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7131045 (or 7131042 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 128358666 is about 11329.5483581650. The cubic root of 128358666 is about 504.4387006051.

The spelling of 128358666 in words is "one hundred twenty-eight million, three hundred fifty-eight thousand, six hundred sixty-six".