217284120832464 has 640 divisors, whose sum is σ = 773813604188160. Its totient is φ = 57013883942400.

The previous prime is 217284120832447. The next prime is 217284120832469. The reversal of 217284120832464 is 464238021482712.

217284120832464 is a `hidden beast` number, since 2 + 1 + 7 + 2 + 84 + 1 + 20 + 83 + 2 + 464 = 666.

It is a super-2 number, since 2×217284120832464² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 217284120832464.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217284120832469) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 273429469 + ... + 274222979.

It is an arithmetic number, because the mean of its divisors is an integer number (1209083756544).

Almost surely, 2^{217284120832464} is an apocalyptic number.

217284120832464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217284120832464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386906802094080).

217284120832464 is an abundant number, since it is smaller than the sum of its proper divisors (556529483355696).

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

217284120832464 is a wasteful number, since it uses less digits than its factorization.

217284120832464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 793716 (or 793704 counting only the distinct ones).

The product of its (nonzero) digits is 8257536, while the sum is 54.

The spelling of 217284120832464 in words is "two hundred seventeen trillion, two hundred eighty-four billion, one hundred twenty million, eight hundred thirty-two thousand, four hundred sixty-four".