647287 has 4 divisors (see below), whose sum is σ = 657016. Its totient is φ = 637560.

The previous prime is 647263. The next prime is 647293. The reversal of 647287 is 782746.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 782746 = 2 ⋅391373.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4764 + ... + 4897.

It is an arithmetic number, because the mean of its divisors is an integer number (164254).

2⁶⁴⁷²⁸⁷ is an apocalyptic number.

647287 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

647287 is a deficient number, since it is larger than the sum of its proper divisors (9729).

647287 is an equidigital number, since it uses as much as digits as its factorization.

647287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9728.

The product of its digits is 18816, while the sum is 34.

The square root of 647287 is about 804.5414843251. The cubic root of 647287 is about 86.5032241773.

The spelling of 647287 in words is "six hundred forty-seven thousand, two hundred eighty-seven".