20106 has 12 divisors (see below), whose sum is σ = 43602.
Its totient is φ = 6696.
The previous prime is 20101. The next prime is 20107. The reversal of 20106 is 60102.
It can be written as a sum of positive squares in only one way, i.e., 19881 + 225 = 141^2 + 15^2
It is a Harshad number since it is a multiple of its sum of digits (9).
It is a Curzon number.
It is a nialpdrome in base 12.
It is not an unprimeable number, because it can be changed into a prime (20101) by changing a digit.
20106 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 541 + ... + 576.
220106 is an apocalyptic number.
20106 is an abundant number, since it is smaller than the sum of its proper divisors (23496).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
20106 is a wasteful number, since it uses less digits than its factorization.
20106 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1125 (or 1122 counting only the distinct ones).
The product of its (nonzero) digits is 12, while the sum is 9.
The square root of 20106 is about 141.7956275772.
The cubic root of 20106 is about 27.1920464058.
Adding to 20106 its reverse (60102), we get a palindrome (80208).
It can be divided in two parts, 2010 and 6, that added together give a triangular number (2016 = T63).
The spelling of 20106 in words is "twenty thousand, one hundred six".