20666684 has 6 divisors (see below), whose sum is σ = 36166704. Its totient is φ = 10333340.

The previous prime is 20666671. The next prime is 20666687. The reversal of 20666684 is 48666602.

It is a super-2 number, since 2×20666684² = 854223655111712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20666687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2583332 + ... + 2583339.

It is an arithmetic number, because the mean of its divisors is an integer number (6027784).

Almost surely, 2^20666684 is an apocalyptic number.

It is an amenable number.

20666684 is a deficient number, since it is larger than the sum of its proper divisors (15500020).

20666684 is a wasteful number, since it uses less digits than its factorization.

20666684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5166675 (or 5166673 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 20666684 is about 4546.0624720740. The cubic root of 20666684 is about 274.4249537439.

The spelling of 20666684 in words is "twenty million, six hundred sixty-six thousand, six hundred eighty-four".