6666559201 has 3 divisors (see below), whose sum is σ = 6666640851. Its totient is φ = 6666477552.

The previous prime is 6666559199. The next prime is 6666559219. The reversal of 6666559201 is 1029556666.

It is a happy number.

The square root of 6666559201 is 81649.

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 can be written as a sum of positive squares in only one way, i.e., 5647672801 + 1018886400 = 75151^2 + 31920^2 .

It is not a de Polignac number, because 6666559201 - 2¹ = 6666559199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6666559301) 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 2 ways as a sum of consecutive naturals, for example, 40825 + ... + 122473.

It is an arithmetic number, because the mean of its divisors is an integer number (2222213617).

Almost surely, 2^6666559201 is an apocalyptic number.

6666559201 is the 81649-th square number.

6666559201 is the 40825-th centered octagonal number.

It is an amenable number.

6666559201 is a deficient number, since it is larger than the sum of its proper divisors (81650).

6666559201 is an frugal number, since it uses more digits than its factorization.

6666559201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163298 (or 81649 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 46.

The cubic root of 6666559201 is about 1882.0619448013.

The spelling of 6666559201 in words is "six billion, six hundred sixty-six million, five hundred fifty-nine thousand, two hundred one".