20873666 has 16 divisors (see below), whose sum is σ = 35955360. Its totient is φ = 8988480.

The previous prime is 20873663. The next prime is 20873681. The reversal of 20873666 is 66637802.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20873663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24551 + ... + 25386.

It is an arithmetic number, because the mean of its divisors is an integer number (2247210).

Almost surely, 2^20873666 is an apocalyptic number.

20873666 is a deficient number, since it is larger than the sum of its proper divisors (15081694).

20873666 is a wasteful number, since it uses less digits than its factorization.

20873666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49969.

The product of its (nonzero) digits is 72576, while the sum is 38.

The square root of 20873666 is about 4568.7707318271. The cubic root of 20873666 is about 275.3380569842.

It can be divided in two parts, 208736 and 66, that added together give a palindrome (208802).

The spelling of 20873666 in words is "twenty million, eight hundred seventy-three thousand, six hundred sixty-six".