285438021 has 8 divisors (see below), whose sum is σ = 415182624. Its totient is φ = 172992720.

The previous prime is 285438001. The next prime is 285438053. The reversal of 285438021 is 120834582.

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

It is not a de Polignac number, because 285438021 - 2¹⁰ = 285436997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 8649637 = 285438021 / (2 + 8 + 5 + 4 + 3 + 8 + 0 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285438001) 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, 4324786 + ... + 4324851.

It is an arithmetic number, because the mean of its divisors is an integer number (51897828).

Almost surely, 2^285438021 is an apocalyptic number.

It is an amenable number.

285438021 is a deficient number, since it is larger than the sum of its proper divisors (129744603).

285438021 is a wasteful number, since it uses less digits than its factorization.

285438021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8649651.

The product of its (nonzero) digits is 15360, while the sum is 33.

The square root of 285438021 is about 16894.9110977241. The cubic root of 285438021 is about 658.4214040732.

The spelling of 285438021 in words is "two hundred eighty-five million, four hundred thirty-eight thousand, twenty-one".