217197997 has 8 divisors (see below), whose sum is σ = 224407040. Its totient is φ = 210001680.

The previous prime is 217197983. The next prime is 217198021. The reversal of 217197997 is 799791712.

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

It is a cyclic number.

It is not a de Polignac number, because 217197997 - 2¹¹ = 217195949 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 (217197977) 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, 41848 + ... + 46750.

It is an arithmetic number, because the mean of its divisors is an integer number (28050880).

Almost surely, 2^217197997 is an apocalyptic number.

It is an amenable number.

217197997 is a deficient number, since it is larger than the sum of its proper divisors (7209043).

217197997 is a wasteful number, since it uses less digits than its factorization.

217197997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6363.

The product of its digits is 500094, while the sum is 52.

The square root of 217197997 is about 14737.6387864542. The cubic root of 217197997 is about 601.1072120272.

The spelling of 217197997 in words is "two hundred seventeen million, one hundred ninety-seven thousand, nine hundred ninety-seven".