66681006807081 has 8 divisors (see below), whose sum is σ = 88913215445824. Its totient is φ = 44451401353200.

The previous prime is 66681006807053. The next prime is 66681006807097. The reversal of 66681006807081 is 18070860018666.

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

It is not a de Polignac number, because 66681006807081 - 2⁹ = 66681006806569 is a prime.

It is a super-2 number, since 2×66681006807081² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66681006807001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 650736445 + ... + 650838906.

It is an arithmetic number, because the mean of its divisors is an integer number (11114151930728).

Almost surely, 2^{66681006807081} is an apocalyptic number.

It is an amenable number.

66681006807081 is a deficient number, since it is larger than the sum of its proper divisors (22232208638743).

66681006807081 is a wasteful number, since it uses less digits than its factorization.

66681006807081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1301592431.

The product of its (nonzero) digits is 4644864, while the sum is 57.

The spelling of 66681006807081 in words is "sixty-six trillion, six hundred eighty-one billion, six million, eight hundred seven thousand, eighty-one".