6506556666 has 8 divisors (see below), whose sum is σ = 13013113344. Its totient is φ = 2168852220.

The previous prime is 6506556599. The next prime is 6506556689. The reversal of 6506556666 is 6666556056.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

6506556666 is an admirable number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 542213050 + ... + 542213061.

It is an arithmetic number, because the mean of its divisors is an integer number (1626639168).

Almost surely, 2^6506556666 is an apocalyptic number.

6506556666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6506556666 is a wasteful number, since it uses less digits than its factorization.

6506556666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1084426116.

The product of its (nonzero) digits is 5832000, while the sum is 51.

The square root of 6506556666 is about 80663.2299502072. The cubic root of 6506556666 is about 1866.8828759696.

The spelling of 6506556666 in words is "six billion, five hundred six million, five hundred fifty-six thousand, six hundred sixty-six".