20566666 has 8 divisors (see below), whose sum is σ = 31602564. Its totient is φ = 10032480.

The previous prime is 20566657. The next prime is 20566673. The reversal of 20566666 is 66666502.

It can be written as a sum of positive squares in 2 ways, for example, as 20566225 + 441 = 4535^2 + 21^2 .

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

20566666 is a modest number, since divided by 6666 gives 2056 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125325 + ... + 125488.

Almost surely, 2^20566666 is an apocalyptic number.

20566666 is a deficient number, since it is larger than the sum of its proper divisors (11035898).

20566666 is a wasteful number, since it uses less digits than its factorization.

20566666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250856.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 20566666 is about 4535.0486215696. The cubic root of 20566666 is about 273.9815374634.

The spelling of 20566666 in words is "twenty million, five hundred sixty-six thousand, six hundred sixty-six".