5515555666 has 8 divisors (see below), whose sum is σ = 8277994620. Its totient is φ = 2756224128.

The previous prime is 5515555607. The next prime is 5515555673. The reversal of 5515555666 is 6665555155.

It can be written as a sum of positive squares in 2 ways, for example, as 5449540041 + 66015625 = 73821^2 + 8125^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 772411 + ... + 779518.

Almost surely, 2^5515555666 is an apocalyptic number.

5515555666 is a deficient number, since it is larger than the sum of its proper divisors (2762438954).

5515555666 is a wasteful number, since it uses less digits than its factorization.

5515555666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1553708.

The product of its digits is 3375000, while the sum is 49.

The square root of 5515555666 is about 74266.7870989448. The cubic root of 5515555666 is about 1766.8367502955.

The spelling of 5515555666 in words is "five billion, five hundred fifteen million, five hundred fifty-five thousand, six hundred sixty-six".