191982217 has 8 divisors (see below), whose sum is σ = 221136896. Its totient is φ = 163259712.

The previous prime is 191982187. The next prime is 191982221. The reversal of 191982217 is 712289191.

191982217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-191982217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 191982217.

It is not an unprimeable number, because it can be changed into a prime (191982257) 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, 107088 + ... + 108865.

It is an arithmetic number, because the mean of its divisors is an integer number (27642112).

Almost surely, 2^191982217 is an apocalyptic number.

It is an amenable number.

191982217 is a deficient number, since it is larger than the sum of its proper divisors (29154679).

191982217 is a wasteful number, since it uses less digits than its factorization.

191982217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216087.

The product of its digits is 18144, while the sum is 40.

The square root of 191982217 is about 13855.7647569522. The cubic root of 191982217 is about 576.8820167924.

The spelling of 191982217 in words is "one hundred ninety-one million, nine hundred eighty-two thousand, two hundred seventeen".