• 287 can be written using four 4's:
287 has 4 divisors (see below), whose sum is σ = 336. Its totient is φ = 240.
The previous prime is 283. The next prime is 293. The reversal of 287 is 782.
287 is nontrivially palindromic in base 13.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 287 - 22 = 283 is a prime.
It is a Kynea number, being equal to (24 + 1)2 - 2.
287 is an undulating number in base 13.
It is a plaindrome in base 6, base 9, base 12, base 14 and base 16.
It is a zygodrome in base 6.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (281) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14 + ... + 27.
It is an arithmetic number, because the mean of its divisors is an integer number (84).
2287 is an apocalyptic number.
287 is the 14-th pentagonal number.
287 is a deficient number, since it is larger than the sum of its proper divisors (49).
287 is an equidigital number, since it uses as much as digits as its factorization.
287 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 48.
The product of its digits is 112, while the sum is 17.
The square root of 287 is about 16.9410743461. The cubic root of 287 is about 6.5962022841.
It can be divided in two parts, 28 and 7, that multiplied together give a square (196 = 142).
The spelling of 287 in words is "two hundred eighty-seven", and thus it is an aban number.
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