20002 has 8 divisors (see below), whose sum is σ = 30636. Its totient is φ = 9792.

The previous prime is 19997. The next prime is 20011.

20002 = T₉₈ + T₉₉ + ... + T₁₀₁.

20002 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 19881 + 121 = 141^2 + 11^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 19973 and 20000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2) 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, 78 + ... + 214.

2²⁰⁰⁰² is an apocalyptic number.

20002 is a deficient number, since it is larger than the sum of its proper divisors (10634).

20002 is a wasteful number, since it uses less digits than its factorization.

20002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212.

The product of its (nonzero) digits is 4, while the sum is 4.

The square root of 20002 is about 141.4284271284. The cubic root of 20002 is about 27.1450809417.

It can be divided in two parts, 2000 and 2, that added together give a palindrome (2002).

The spelling of 20002 in words is "twenty thousand, two", and thus it is an iban number.