6863975566561 has 3 divisors (see below), whose sum is σ = 6863978186481. Its totient is φ = 6863972946642.

The previous prime is 6863975566559. The next prime is 6863975566573. The reversal of 6863975566561 is 1656655793686.

The square root of 6863975566561 is 2619919.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 6863975566561 - 2¹ = 6863975566559 is a prime.

It is a super-2 number, since 2×6863975566561² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6863975566501) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1309960 + ... + 3929878.

It is an arithmetic number, because the mean of its divisors is an integer number (2287992728827).

Almost surely, 2^{6863975566561} is an apocalyptic number.

6863975566561 is the 2619919-th square number.

6863975566561 is the 1309960-th centered octagonal number.

It is an amenable number.

6863975566561 is a deficient number, since it is larger than the sum of its proper divisors (2619920).

6863975566561 is an frugal number, since it uses more digits than its factorization.

6863975566561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5239838 (or 2619919 counting only the distinct ones).

The product of its digits is 1469664000, while the sum is 73.

The spelling of 6863975566561 in words is "six trillion, eight hundred sixty-three billion, nine hundred seventy-five million, five hundred sixty-six thousand, five hundred sixty-one".