66562765668 has 144 divisors (see below), whose sum is σ = 204073309440. Its totient is φ = 17857953792.

The previous prime is 66562765657. The next prime is 66562765669. The reversal of 66562765668 is 86656726566.

It is a happy number.

66562765668 is a `hidden beast` number, since 6 + 6 + 5 + 62 + 7 + 6 + 566 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (66562765669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1862980 + ... + 1898372.

It is an arithmetic number, because the mean of its divisors is an integer number (1417175760).

Almost surely, 2^66562765668 is an apocalyptic number.

66562765668 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66562765668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102036654720).

66562765668 is an abundant number, since it is smaller than the sum of its proper divisors (137510543772).

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

66562765668 is a wasteful number, since it uses less digits than its factorization.

66562765668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35866 (or 35861 counting only the distinct ones).

The product of its digits is 130636800, while the sum is 63.

The spelling of 66562765668 in words is "sixty-six billion, five hundred sixty-two million, seven hundred sixty-five thousand, six hundred sixty-eight".