20243 has 4 divisors (see below), whose sum is σ = 20928.
Its totient is φ = 19560.
The previous prime is 20233. The next prime is 20249. The reversal of 20243 is 34202.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 20243 - 210 = 19219 is a prime.
It is a d-powerful number, because it can be written as 25 + 0 + 29 + 42 + 39 .
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (20249) 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, 296 + ... + 357.
It is an arithmetic number, because the mean of its divisors is an integer number (5232).
220243 is an apocalyptic number.
20243 is a deficient number, since it is larger than the sum of its proper divisors (685).
20243 is an equidigital number, since it uses as much as digits as its factorization.
20243 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 684.
The product of its (nonzero) digits is 48, while the sum is 11.
The square root of 20243 is about 142.2778970888.
The cubic root of 20243 is about 27.2536678283.
Adding to 20243 its reverse (34202), we get a palindrome (54445).
The spelling of 20243 in words is "twenty thousand, two hundred forty-three", and thus it is an iban number.