20286643 has 4 divisors (see below), whose sum is σ = 21847168. Its totient is φ = 18726120.

The previous prime is 20286613. The next prime is 20286653. The reversal of 20286643 is 34668202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20286643 - 2⁹ = 20286131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20286613) 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, 780243 + ... + 780268.

It is an arithmetic number, because the mean of its divisors is an integer number (5461792).

Almost surely, 2^20286643 is an apocalyptic number.

20286643 is a deficient number, since it is larger than the sum of its proper divisors (1560525).

20286643 is a wasteful number, since it uses less digits than its factorization.

20286643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560524.

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 20286643 is about 4504.0696042579. The cubic root of 20286643 is about 272.7323966478.

The spelling of 20286643 in words is "twenty million, two hundred eighty-six thousand, six hundred forty-three".