20685668 has 24 divisors (see below), whose sum is σ = 38701152. Its totient is φ = 9640064.

The previous prime is 20685659. The next prime is 20685683. The reversal of 20685668 is 86658602.

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 7 ways as a sum of consecutive naturals, for example, 5855 + ... + 8697.

It is an arithmetic number, because the mean of its divisors is an integer number (1612548).

Almost surely, 2^20685668 is an apocalyptic number.

It is an amenable number.

20685668 is a deficient number, since it is larger than the sum of its proper divisors (18015484).

20685668 is a wasteful number, since it uses less digits than its factorization.

20685668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2971 (or 2969 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 20685668 is about 4548.1499535525. The cubic root of 20685668 is about 274.5089551084.

The spelling of 20685668 in words is "twenty million, six hundred eighty-five thousand, six hundred sixty-eight".