66281 has 4 divisors (see below), whose sum is σ = 67200. Its totient is φ = 65364.

The previous prime is 66271. The next prime is 66293. The reversal of 66281 is 18266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18266 = 2 ⋅9133.

It is a cyclic number.

It is not a de Polignac number, because 66281 - 2¹⁰ = 65257 is a prime.

It is a super-2 number, since 2×66281² = 8786341922, which contains 22 as substring.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 66281.

It is not an unprimeable number, because it can be changed into a prime (66221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 341 + ... + 498.

It is an arithmetic number, because the mean of its divisors is an integer number (16800).

2⁶⁶²⁸¹ is an apocalyptic number.

It is an amenable number.

66281 is a deficient number, since it is larger than the sum of its proper divisors (919).

66281 is an equidigital number, since it uses as much as digits as its factorization.

66281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918.

The product of its digits is 576, while the sum is 23.

The square root of 66281 is about 257.4509662052. The cubic root of 66281 is about 40.4696719552.

The spelling of 66281 in words is "sixty-six thousand, two hundred eighty-one".