217165542722 has 6 divisors (see below), whose sum is σ = 325749302643. Its totient is φ = 108582441842.

The previous prime is 217165542721. The next prime is 217165542751. The reversal of 217165542722 is 227245561712.

It can be written as a sum of positive squares in only one way, i.e., 108582771361 + 108582771361 = 329519^2 + 329519^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=329519.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217165542721) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 494279 + ... + 823797.

Almost surely, 2^217165542722 is an apocalyptic number.

217165542722 is a deficient number, since it is larger than the sum of its proper divisors (108583759921).

217165542722 is an frugal number, since it uses more digits than its factorization.

217165542722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659040 (or 329521 counting only the distinct ones).

The product of its digits is 470400, while the sum is 44.

The spelling of 217165542722 in words is "two hundred seventeen billion, one hundred sixty-five million, five hundred forty-two thousand, seven hundred twenty-two".