286640 has 20 divisors (see below), whose sum is σ = 666624. Its totient is φ = 114624.

The previous prime is 286633. The next prime is 286651. The reversal of 286640 is 46682.

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a nialpdrome in base 14.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 286640.

It is an unprimeable number.

286640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1712 + ... + 1871.

2²⁸⁶⁶⁴⁰ is an apocalyptic number.

286640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

286640 is an abundant number, since it is smaller than the sum of its proper divisors (379984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

286640 is a wasteful number, since it uses less digits than its factorization.

286640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3596 (or 3590 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 286640 is about 535.3877099822. The cubic root of 286640 is about 65.9344313614.

The spelling of 286640 in words is "two hundred eighty-six thousand, six hundred forty".