20818218 has 8 divisors (see below), whose sum is σ = 41636448. Its totient is φ = 6939404.

The previous prime is 20818211. The next prime is 20818223. The reversal of 20818218 is 81281802.

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

20818218 is an admirable number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20818211) 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 3 ways as a sum of consecutive naturals, for example, 1734846 + ... + 1734857.

It is an arithmetic number, because the mean of its divisors is an integer number (5204556).

Almost surely, 2^20818218 is an apocalyptic number.

20818218 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20818218 is a wasteful number, since it uses less digits than its factorization.

20818218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3469708.

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 20818218 is about 4562.6985436253. The cubic root of 20818218 is about 275.0940416661.

The spelling of 20818218 in words is "twenty million, eight hundred eighteen thousand, two hundred eighteen".