20216818 has 8 divisors (see below), whose sum is σ = 30417840. Its totient is φ = 10077540.

The previous prime is 20216761. The next prime is 20216827. The reversal of 20216818 is 81861202.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14608 + ... + 15931.

It is an arithmetic number, because the mean of its divisors is an integer number (3802230).

Almost surely, 2^20216818 is an apocalyptic number.

20216818 is a deficient number, since it is larger than the sum of its proper divisors (10201022).

20216818 is a wasteful number, since it uses less digits than its factorization.

20216818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30872.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 20216818 is about 4496.3115995224. The cubic root of 20216818 is about 272.4191292720.

It can be divided in two parts, 202 and 16818, that added together give a triangular number (17020 = T₁₈₄).

The spelling of 20216818 in words is "twenty million, two hundred sixteen thousand, eight hundred eighteen".