217155764512828 has 24 divisors (see below), whose sum is σ = 384836468486400. Its totient is φ = 107202512574768.

The previous prime is 217155764512787. The next prime is 217155764512829. The reversal of 217155764512828 is 828215467551712.

It is a happy number.

It is a super-2 number, since 2×217155764512828² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 217155764512828.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217155764512829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32676543 + ... + 38756521.

It is an arithmetic number, because the mean of its divisors is an integer number (16034852853600).

Almost surely, 2^{217155764512828} is an apocalyptic number.

It is an amenable number.

217155764512828 is a deficient number, since it is larger than the sum of its proper divisors (167680703973572).

217155764512828 is a wasteful number, since it uses less digits than its factorization.

217155764512828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6193089 (or 6193087 counting only the distinct ones).

The product of its digits is 75264000, while the sum is 64.

The spelling of 217155764512828 in words is "two hundred seventeen trillion, one hundred fifty-five billion, seven hundred sixty-four million, five hundred twelve thousand, eight hundred twenty-eight".