217243014375556 has 45 divisors (see below), whose sum is σ = 411864883763459. Its totient is φ = 100263707324976.

The previous prime is 217243014375551. The next prime is 217243014375571. The reversal of 217243014375556 is 655573410342712.

The square root of 217243014375556 is 14739166.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 107712556513156 + 109530457862400 = 10378466^2 + 10465680^2 .

It is a super-2 number, since 2×217243014375556² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 217243014375497 and 217243014375506.

It is not an unprimeable number, because it can be changed into a prime (217243014375551) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 4981816305 + ... + 4981859911.

Almost surely, 2^{217243014375556} is an apocalyptic number.

217243014375556 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

217243014375556 is the 14739166-th square number.

It is an amenable number.

217243014375556 is a deficient number, since it is larger than the sum of its proper divisors (194621869387903).

217243014375556 is an frugal number, since it uses more digits than its factorization.

217243014375556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87270 (or 43622 counting only the distinct ones).

The product of its (nonzero) digits is 21168000, while the sum is 55.

The spelling of 217243014375556 in words is "two hundred seventeen trillion, two hundred forty-three billion, fourteen million, three hundred seventy-five thousand, five hundred fifty-six".