20606 has 4 divisors (see below), whose sum is σ = 30912.
Its totient is φ = 10302.
The previous prime is 20599. The next prime is 20611. The reversal of 20606 is 60602.
It is a semiprime because it is the product of two primes.
20606 is a modest number, since divided by 606 gives 2 as remainder.
It is a Curzon number.
It is a congruent number.
It is an unprimeable number.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5150 + ... + 5153.
It is an arithmetic number, because the mean of its divisors is an integer number (7728).
220606 is an apocalyptic number.
20606 is a deficient number, since it is larger than the sum of its proper divisors (10306).
20606 is a wasteful number, since it uses less digits than its factorization.
20606 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 10305.
The product of its (nonzero) digits is 72, while the sum is 14.
The square root of 20606 is about 143.5479014127.
The cubic root of 20606 is about 27.4156090578.
It can be divided in two parts, 20 and 606, that added together give a palindrome (626).
The spelling of 20606 in words is "twenty thousand, six hundred six".