66681982695 has 8 divisors (see below), whose sum is σ = 106691172336. Its totient is φ = 35563724096.

The previous prime is 66681982667. The next prime is 66681982721. The reversal of 66681982695 is 59628918666.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 66681982695 - 2⁵ = 66681982663 is a prime.

It is a super-2 number, since 2×66681982695² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2222732742 + ... + 2222732771.

It is an arithmetic number, because the mean of its divisors is an integer number (13336396542).

Almost surely, 2^66681982695 is an apocalyptic number.

66681982695 is a deficient number, since it is larger than the sum of its proper divisors (40009189641).

66681982695 is a wasteful number, since it uses less digits than its factorization.

66681982695 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4445465521.

The product of its digits is 67184640, while the sum is 66.

The spelling of 66681982695 in words is "sixty-six billion, six hundred eighty-one million, nine hundred eighty-two thousand, six hundred ninety-five".