287091 has 32 divisors (see below), whose sum is σ = 512000. Its totient is φ = 158760.

The previous prime is 287087. The next prime is 287093. The reversal of 287091 is 190782.

It is not a de Polignac number, because 287091 - 2² = 287087 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

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 287091.

It is not an unprimeable number, because it can be changed into a prime (287093) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9246 + ... + 9276.

It is an arithmetic number, because the mean of its divisors is an integer number (16000).

2²⁸⁷⁰⁹¹ is an apocalyptic number.

287091 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

287091 is a deficient number, since it is larger than the sum of its proper divisors (224909).

287091 is an equidigital number, since it uses as much as digits as its factorization.

287091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 287091 is about 535.8087345313. The cubic root of 287091 is about 65.9689937002.

The spelling of 287091 in words is "two hundred eighty-seven thousand, ninety-one".