7667992997666 has 4 divisors (see below), whose sum is σ = 11501989496502. Its totient is φ = 3833996498832.

The previous prime is 7667992997663. The next prime is 7667992997711. The reversal of 7667992997666 is 6667992997667.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 4555573715641 + 3112419282025 = 2134379^2 + 1764205^2 .

It is a super-2 number, since 2×7667992997666² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (7667992997663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1916998249415 + ... + 1916998249418.

Almost surely, 2^{7667992997666} is an apocalyptic number.

7667992997666 is a deficient number, since it is larger than the sum of its proper divisors (3833996498836).

7667992997666 is a wasteful number, since it uses less digits than its factorization.

7667992997666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3833996498835.

The product of its digits is 34998578496, while the sum is 89.

Subtracting from 7667992997666 its reverse (6667992997667), we obtain a palindrome (999999999999).

The spelling of 7667992997666 in words is "seven trillion, six hundred sixty-seven billion, nine hundred ninety-two million, nine hundred ninety-seven thousand, six hundred sixty-six".