20216859 has 16 divisors (see below), whose sum is σ = 30737952. Its totient is φ = 11708928.

The previous prime is 20216851. The next prime is 20216863. The reversal of 20216859 is 95861202.

It is not a de Polignac number, because 20216859 - 2³ = 20216851 is a prime.

It is a super-3 number, since 3×20216859³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20216851) 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 15 ways as a sum of consecutive naturals, for example, 14584 + ... + 15909.

It is an arithmetic number, because the mean of its divisors is an integer number (1921122).

Almost surely, 2^20216859 is an apocalyptic number.

20216859 is a deficient number, since it is larger than the sum of its proper divisors (10521093).

20216859 is a wasteful number, since it uses less digits than its factorization.

20216859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30526.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 20216859 is about 4496.3161588127. The cubic root of 20216859 is about 272.4193134286.

The spelling of 20216859 in words is "twenty million, two hundred sixteen thousand, eight hundred fifty-nine".