20201 has 2 divisors, whose sum is σ = 20202. Its totient is φ = 20200.
The previous prime is 20183. The next prime is 20219. The reversal of 20201 is 10202.
It is a balanced prime because it is at equal distance from previous prime (20183) and next prime (20219).
It can be written as a sum of positive squares in only one way, i.e., 10201 + 10000 = 101^2 + 100^2 .
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-20201 is a prime.
It is a Chen prime.
It is an Ulam number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (20231) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10100 + 10101.
It is an arithmetic number, because the mean of its divisors is an integer number (10101).
220201 is an apocalyptic number.
20201 is the 101-st centered square number.
It is an amenable number.
20201 is a deficient number, since it is larger than the sum of its proper divisors (1).
20201 is an equidigital number, since it uses as much as digits as its factorization.
20201 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 4, while the sum is 5.
The square root of 20201 is about 142.1302219797. The cubic root of 20201 is about 27.2348062201.
Adding to 20201 its reverse (10202), we get a palindrome (30403).
Subtracting from 20201 its reverse (10202), we obtain a palindrome (9999).
Multiplying 20201 by its reverse (10202), we get a palindrome (206090602).
The spelling of 20201 in words is "twenty thousand, two hundred one", and thus it is an iban number.
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