216685193 has 4 divisors (see below), whose sum is σ = 216727680. Its totient is φ = 216642708.

The previous prime is 216685171. The next prime is 216685199. The reversal of 216685193 is 391586612.

216685193 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 216685193 - 2¹² = 216681097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216685193.

It is not an unprimeable number, because it can be changed into a prime (216685199) 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, 12353 + ... + 24206.

It is an arithmetic number, because the mean of its divisors is an integer number (54181920).

Almost surely, 2^216685193 is an apocalyptic number.

It is an amenable number.

216685193 is a deficient number, since it is larger than the sum of its proper divisors (42487).

216685193 is an equidigital number, since it uses as much as digits as its factorization.

216685193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42486.

The product of its digits is 77760, while the sum is 41.

The square root of 216685193 is about 14720.2307386807. The cubic root of 216685193 is about 600.6337682902.

The spelling of 216685193 in words is "two hundred sixteen million, six hundred eighty-five thousand, one hundred ninety-three".