20008 has 16 divisors (see below), whose sum is σ = 39060. Its totient is φ = 9600.

The previous prime is 19997. The next prime is 20011. The reversal of 20008 is 80002.

It is a happy number.

20008 is nontrivially palindromic in base 3.

It can be written as a sum of positive squares in 2 ways, for example, as 13924 + 6084 = 118^2 + 78^2 .

It is a plaindrome in base 7 and base 15.

It is a zygodrome in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 19976 and 20003.

It is a congruent number.

It is an unprimeable number.

20008 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 298 + ... + 358.

2²⁰⁰⁰⁸ is an apocalyptic number.

20008 is the 82-nd octagonal number.

It is an amenable number.

20008 is a deficient number, since it is larger than the sum of its proper divisors (19052).

20008 is a wasteful number, since it uses less digits than its factorization.

20008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 20008 is about 141.4496376807. The cubic root of 20008 is about 27.1477949070.

The spelling of 20008 in words is "twenty thousand, eight".