87281 has 2 divisors, whose sum is σ = 87282. Its totient is φ = 87280.
The previous prime is 87277. The next prime is 87293. The reversal of 87281 is 18278.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 87025 + 256 = 295^2 + 16^2 .
It is a cyclic number.
It is not a de Polignac number, because 87281 - 22 = 87277 is a prime.
It is a super-2 number, since 2×872812 = 15235945922, which contains 22 as substring.
It is a self number, because there is not a number n which added to its sum of digits gives 87281.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 87281.
It is not a weakly prime, because it can be changed into another prime (87211) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43640 + 43641.
It is an arithmetic number, because the mean of its divisors is an integer number (43641).
287281 is an apocalyptic number.
It is an amenable number.
87281 is a deficient number, since it is larger than the sum of its proper divisors (1).
87281 is an equidigital number, since it uses as much as digits as its factorization.
87281 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 896, while the sum is 26.
The square root of 87281 is about 295.4335796757. The cubic root of 87281 is about 44.3581308624.
The spelling of 87281 in words is "eighty-seven thousand, two hundred eighty-one".
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