285215221 has 8 divisors (see below), whose sum is σ = 295916544. Its totient is φ = 274607760.

The previous prime is 285215219. The next prime is 285215267. The reversal of 285215221 is 122512582.

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

It is a cyclic number.

It is not a de Polignac number, because 285215221 - 2¹ = 285215219 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 285215221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285215521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17245 + ... + 29458.

It is an arithmetic number, because the mean of its divisors is an integer number (36989568).

Almost surely, 2^285215221 is an apocalyptic number.

It is an amenable number.

285215221 is a deficient number, since it is larger than the sum of its proper divisors (10701323).

285215221 is a wasteful number, since it uses less digits than its factorization.

285215221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46931.

The product of its digits is 3200, while the sum is 28.

The square root of 285215221 is about 16888.3161090738. The cubic root of 285215221 is about 658.2500481655.

The spelling of 285215221 in words is "two hundred eighty-five million, two hundred fifteen thousand, two hundred twenty-one".