217163779293 has 16 divisors (see below), whose sum is σ = 299384569856. Its totient is φ = 139874811120.

The previous prime is 217163779291. The next prime is 217163779379. The reversal of 217163779293 is 392977361712.

It is not a de Polignac number, because 217163779293 - 2¹ = 217163779291 is a prime.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217163779291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1867021 + ... + 1979922.

It is an arithmetic number, because the mean of its divisors is an integer number (18711535616).

Almost surely, 2^217163779293 is an apocalyptic number.

It is an amenable number.

217163779293 is a deficient number, since it is larger than the sum of its proper divisors (82220790563).

217163779293 is a wasteful number, since it uses less digits than its factorization.

217163779293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3847584.

The product of its digits is 6001128, while the sum is 57.

The spelling of 217163779293 in words is "two hundred seventeen billion, one hundred sixty-three million, seven hundred seventy-nine thousand, two hundred ninety-three".