20786 has 8 divisors (see below), whose sum is σ = 32880. Its totient is φ = 9828.

The previous prime is 20773. The next prime is 20789. The reversal of 20786 is 68702.

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

It is not an unprimeable number, because it can be changed into a prime (20789) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 236 + ... + 311.

It is an arithmetic number, because the mean of its divisors is an integer number (4110).

2²⁰⁷⁸⁶ is an apocalyptic number.

20786 is a deficient number, since it is larger than the sum of its proper divisors (12094).

20786 is a wasteful number, since it uses less digits than its factorization.

20786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 568.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 20786 is about 144.1735065815. The cubic root of 20786 is about 27.4952057758.

The spelling of 20786 in words is "twenty thousand, seven hundred eighty-six".