217131383 has 4 divisors (see below), whose sum is σ = 248150160. Its totient is φ = 186112608.

The previous prime is 217131377. The next prime is 217131413. The reversal of 217131383 is 383131712.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 217131383 - 2⁶ = 217131319 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217131883) 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, 15509378 + ... + 15509391.

It is an arithmetic number, because the mean of its divisors is an integer number (62037540).

Almost surely, 2^217131383 is an apocalyptic number.

217131383 is a deficient number, since it is larger than the sum of its proper divisors (31018777).

217131383 is an equidigital number, since it uses as much as digits as its factorization.

217131383 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31018776.

The product of its digits is 3024, while the sum is 29.

The square root of 217131383 is about 14735.3786174635. The cubic root of 217131383 is about 601.0457531269.

The spelling of 217131383 in words is "two hundred seventeen million, one hundred thirty-one thousand, three hundred eighty-three".