217393 has 4 divisors (see below), whose sum is σ = 237168. Its totient is φ = 197620.

The previous prime is 217387. The next prime is 217397. The reversal of 217393 is 393712.

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 217393 - 2⁵ = 217361 is a prime.

It is a Duffinian number.

217393 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (217397) 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, 9871 + ... + 9892.

It is an arithmetic number, because the mean of its divisors is an integer number (59292).

2²¹⁷³⁹³ is an apocalyptic number.

It is an amenable number.

217393 is a deficient number, since it is larger than the sum of its proper divisors (19775).

217393 is a wasteful number, since it uses less digits than its factorization.

217393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19774.

The product of its digits is 1134, while the sum is 25.

The square root of 217393 is about 466.2542225010. The cubic root of 217393 is about 60.1287052003.

The spelling of 217393 in words is "two hundred seventeen thousand, three hundred ninety-three".