217923488364672 has 768 divisors, whose sum is σ = 663865850419200. Its totient is φ = 68529111146496.

The previous prime is 217923488364643. The next prime is 217923488364683. The reversal of 217923488364672 is 276463884329712.

217923488364672 is a `hidden beast` number, since 2 + 1 + 7 + 9 + 2 + 3 + 488 + 36 + 46 + 72 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 217923488364672.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 194054753103 + ... + 194054754225.

It is an arithmetic number, because the mean of its divisors is an integer number (864408659400).

Almost surely, 2^{217923488364672} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217923488364672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (331932925209600).

217923488364672 is an abundant number, since it is smaller than the sum of its proper divisors (445942362054528).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217923488364672 is a wasteful number, since it uses less digits than its factorization.

217923488364672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1905 (or 1890 counting only the distinct ones).

The product of its digits is 1170505728, while the sum is 72.

The spelling of 217923488364672 in words is "two hundred seventeen trillion, nine hundred twenty-three billion, four hundred eighty-eight million, three hundred sixty-four thousand, six hundred seventy-two".