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8281 = 72132
BaseRepresentation
bin10000001011001
3102100201
42001121
5231111
6102201
733100
oct20131
912321
108281
116249
124961
133a00
143037
1526c1
hex2059

8281 has 9 divisors (see below), whose sum is σ = 10431. Its totient is φ = 6552.

The previous prime is 8273. The next prime is 8287. The reversal of 8281 is 1828.

8281 = T29 + T30 + ... + T41.

8281 = 13 + 23 + ... + 133.

It is a happy number.

The square root of 8281 is 91.

It is a perfect power (a square), and thus also a powerful number.

8281 is nontrivially palindromic in base 6 and base 9.

8281 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 1225 + 7056 = 35^2 + 84^2 .

It is not a de Polignac number, because 8281 - 23 = 8273 is a prime.

It is a super-2 number, since 2×82812 = 137149922, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (8287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 631 + ... + 643.

It is an arithmetic number, because the mean of its divisors is an integer number (1159).

28281 is an apocalyptic number.

8281 is the 91-st square number and also the 49-th nonagonal number.

8281 is the 46-th centered octagonal number.

It is an amenable number.

8281 is a deficient number, since it is larger than the sum of its proper divisors (2150).

8281 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (8280) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (40).

8281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40 (or 20 counting only the distinct ones).

The product of its digits is 128, while the sum is 19.

The cubic root of 8281 is about 20.2314772451.

It can be divided in two parts, 8 and 281, that added together give a square (289 = 172).

The spelling of 8281 in words is "eight thousand, two hundred eighty-one".

Divisors: 1 7 13 49 91 169 637 1183 8281