6651998991566 has 8 divisors (see below), whose sum is σ = 10044964920600. Its totient is φ = 3303677351368.

The previous prime is 6651998991509. The next prime is 6651998991601.

6651998991566 is nontrivially palindromic in base 10.

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

It is a super-4 number, since 4×6651998991566⁴ (a number of 52 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 11161071836 + ... + 11161072431.

It is an arithmetic number, because the mean of its divisors is an integer number (1255620615075).

Almost surely, 2^{6651998991566} is an apocalyptic number.

6651998991566 is a deficient number, since it is larger than the sum of its proper divisors (3392965929034).

6651998991566 is a wasteful number, since it uses less digits than its factorization.

6651998991566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22322144418.

The product of its digits is 1700611200, while the sum is 80.

The spelling of 6651998991566 in words is "six trillion, six hundred fifty-one billion, nine hundred ninety-eight million, nine hundred ninety-one thousand, five hundred sixty-six".