81223 has 2 divisors, whose sum is σ = 81224. Its totient is φ = 81222.
The previous prime is 81203. The next prime is 81233. The reversal of 81223 is 32218.
It is a happy number.
It is a strong prime.
81223 is a truncatable prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-81223 is a prime.
It is a plaindrome in base 9.
It is a junction number, because it is equal to n+sod(n) for n = 81197 and 81206.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (81203) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40611 + 40612.
It is an arithmetic number, because the mean of its divisors is an integer number (40612).
281223 is an apocalyptic number.
81223 is a deficient number, since it is larger than the sum of its proper divisors (1).
81223 is an equidigital number, since it uses as much as digits as its factorization.
81223 is an evil number, because the sum of its binary digits is even.
The product of its digits is 96, while the sum is 16.
The square root of 81223 is about 284.9964912065. The cubic root of 81223 is about 43.3071571035.
The spelling of 81223 in words is "eighty-one thousand, two hundred twenty-three".
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