6566561243 has 16 divisors (see below), whose sum is σ = 7398190080. Its totient is φ = 5776900800.

The previous prime is 6566561237. The next prime is 6566561279. The reversal of 6566561243 is 3421656656.

It is not a de Polignac number, because 6566561243 - 2¹⁸ = 6566299099 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6566561194 and 6566561203.

It is not an unprimeable number, because it can be changed into a prime (6566561233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25343 + ... + 117368.

It is an arithmetic number, because the mean of its divisors is an integer number (462386880).

Almost surely, 2^6566561243 is an apocalyptic number.

6566561243 is a deficient number, since it is larger than the sum of its proper divisors (831628837).

6566561243 is a wasteful number, since it uses less digits than its factorization.

6566561243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142858.

The product of its digits is 777600, while the sum is 44.

The square root of 6566561243 is about 81034.3213891497. The cubic root of 6566561243 is about 1872.6042283440.

The spelling of 6566561243 in words is "six billion, five hundred sixty-six million, five hundred sixty-one thousand, two hundred forty-three".