6681757666 has 8 divisors (see below), whose sum is σ = 10039150080. Its totient is φ = 3335374308.

The previous prime is 6681757627. The next prime is 6681757699. The reversal of 6681757666 is 6667571866.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 6681757666.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2750746 + ... + 2753173.

It is an arithmetic number, because the mean of its divisors is an integer number (1254893760).

Almost surely, 2^6681757666 is an apocalyptic number.

6681757666 is a deficient number, since it is larger than the sum of its proper divisors (3357392414).

6681757666 is a wasteful number, since it uses less digits than its factorization.

6681757666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5504528.

The product of its digits is 15240960, while the sum is 58.

The square root of 6681757666 is about 81742.0189743317. The cubic root of 6681757666 is about 1883.4911049665.

The spelling of 6681757666 in words is "six billion, six hundred eighty-one million, seven hundred fifty-seven thousand, six hundred sixty-six".