66666746680 has 32 divisors (see below), whose sum is σ = 150141651840. Its totient is φ = 26641548160.

The previous prime is 66666746621. The next prime is 66666746689. The reversal of 66666746680 is 8664766666.

It is a super-2 number, since 2×66666746680² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666746689) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 742984 + ... + 827863.

It is an arithmetic number, because the mean of its divisors is an integer number (4691926620).

Almost surely, 2^66666746680 is an apocalyptic number.

It is an amenable number.

66666746680 is an abundant number, since it is smaller than the sum of its proper divisors (83474905160).

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

66666746680 is a wasteful number, since it uses less digits than its factorization.

66666746680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571919 (or 1571915 counting only the distinct ones).

The product of its (nonzero) digits is 62705664, while the sum is 61.

The spelling of 66666746680 in words is "sixty-six billion, six hundred sixty-six million, seven hundred forty-six thousand, six hundred eighty".