285991666 has 8 divisors (see below), whose sum is σ = 432074160. Its totient is φ = 141966948.

The previous prime is 285991661. The next prime is 285991669. The reversal of 285991666 is 666199582.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (285991661) 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, 514096 + ... + 514651.

It is an arithmetic number, because the mean of its divisors is an integer number (54009270).

Almost surely, 2^285991666 is an apocalyptic number.

285991666 is a deficient number, since it is larger than the sum of its proper divisors (146082494).

285991666 is a wasteful number, since it uses less digits than its factorization.

285991666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028888.

The product of its digits is 1399680, while the sum is 52.

The square root of 285991666 is about 16911.2881236173. The cubic root of 285991666 is about 658.8468277603.

The spelling of 285991666 in words is "two hundred eighty-five million, nine hundred ninety-one thousand, six hundred sixty-six".