287864 has 8 divisors (see below), whose sum is σ = 539760. Its totient is φ = 143928.

The previous prime is 287863. The next prime is 287867. The reversal of 287864 is 468782.

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 9.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 287864.

It is not an unprimeable number, because it can be changed into a prime (287863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17984 + ... + 17999.

It is an arithmetic number, because the mean of its divisors is an integer number (67470).

2²⁸⁷⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

287864 is a deficient number, since it is larger than the sum of its proper divisors (251896).

287864 is a wasteful number, since it uses less digits than its factorization.

287864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35989 (or 35985 counting only the distinct ones).

The product of its digits is 21504, while the sum is 35.

The square root of 287864 is about 536.5295891188. The cubic root of 287864 is about 66.0281483851.

The spelling of 287864 in words is "two hundred eighty-seven thousand, eight hundred sixty-four".