285979993 has 12 divisors (see below), whose sum is σ = 316546860. Its totient is φ = 256830912.

The previous prime is 285979987. The next prime is 285980011. The reversal of 285979993 is 399979582.

It can be written as a sum of positive squares in 6 ways, for example, as 4981824 + 280998169 = 2232^2 + 16763^2 .

It is not a de Polignac number, because 285979993 - 2⁹ = 285979481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (285979193) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9763 + ... + 25831.

It is an arithmetic number, because the mean of its divisors is an integer number (26378905).

Almost surely, 2^285979993 is an apocalyptic number.

It is an amenable number.

285979993 is a deficient number, since it is larger than the sum of its proper divisors (30566867).

285979993 is a wasteful number, since it uses less digits than its factorization.

285979993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16156 (or 16119 counting only the distinct ones).

The product of its digits is 11022480, while the sum is 61.

The square root of 285979993 is about 16910.9429955872. The cubic root of 285979993 is about 658.8378638352.

The spelling of 285979993 in words is "two hundred eighty-five million, nine hundred seventy-nine thousand, nine hundred ninety-three".