216285993 has 24 divisors (see below), whose sum is σ = 389503296. Its totient is φ = 112356000.

The previous prime is 216285959. The next prime is 216286013. The reversal of 216285993 is 399582612.

It is not a de Polignac number, because 216285993 - 2¹³ = 216277801 is a prime.

It is a super-3 number, since 3×216285993³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (216285593) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 155358 + ... + 156743.

It is an arithmetic number, because the mean of its divisors is an integer number (16229304).

Almost surely, 2^216285993 is an apocalyptic number.

It is an amenable number.

216285993 is a deficient number, since it is larger than the sum of its proper divisors (173217303).

216285993 is a wasteful number, since it uses less digits than its factorization.

216285993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312125 (or 312122 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The square root of 216285993 is about 14706.6649176487. The cubic root of 216285993 is about 600.2646915468.

The spelling of 216285993 in words is "two hundred sixteen million, two hundred eighty-five thousand, nine hundred ninety-three".