20666668 has 24 divisors (see below), whose sum is σ = 39936960. Its totient is φ = 9279120.

The previous prime is 20666651. The next prime is 20666669. The reversal of 20666668 is 86666602.

It is a super-2 number, since 2×20666668² = 854222332444448, which contains 22 as substring.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20666668.

It is not an unprimeable number, because it can be changed into a prime (20666669) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 823 + ... + 6481.

It is an arithmetic number, because the mean of its divisors is an integer number (1664040).

Almost surely, 2^20666668 is an apocalyptic number.

It is an amenable number.

20666668 is a deficient number, since it is larger than the sum of its proper divisors (19270292).

20666668 is a wasteful number, since it uses less digits than its factorization.

20666668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5757 (or 5755 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 20666668 is about 4546.0607123091. The cubic root of 20666668 is about 274.4248829246.

The spelling of 20666668 in words is "twenty million, six hundred sixty-six thousand, six hundred sixty-eight".