6661555344 has 140 divisors (see below), whose sum is σ = 20370459600. Its totient is φ = 2103579072.

The previous prime is 6661555301. The next prime is 6661555357. The reversal of 6661555344 is 4435551666.

It is a self number, because there is not a number n which added to its sum of digits gives 6661555344.

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 27 ways as a sum of consecutive naturals, for example, 206587 + ... + 236645.

Almost surely, 2^6661555344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6661555344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10185229800).

6661555344 is an abundant number, since it is smaller than the sum of its proper divisors (13708904256).

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

6661555344 is a wasteful number, since it uses less digits than its factorization.

6661555344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30104 (or 30083 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 45.

The square root of 6661555344 is about 81618.3517598830. The cubic root of 6661555344 is about 1881.5909409055.

The spelling of 6661555344 in words is "six billion, six hundred sixty-one million, five hundred fifty-five thousand, three hundred forty-four".