66993611639966 has 32 divisors (see below), whose sum is σ = 109654695571968. Its totient is φ = 30443646752640.

The previous prime is 66993611639963. The next prime is 66993611639993.

66993611639966 is nontrivially palindromic in base 10.

It is a super-3 number, since 3×66993611639966³ (a number of 42 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66993611639963) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1941095126 + ... + 1941129638.

It is an arithmetic number, because the mean of its divisors is an integer number (3426709236624).

Almost surely, 2^{66993611639966} is an apocalyptic number.

66993611639966 is a deficient number, since it is larger than the sum of its proper divisors (42661083932002).

66993611639966 is a wasteful number, since it uses less digits than its factorization.

66993611639966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55136.

The product of its digits is 2754990144, while the sum is 80.

The spelling of 66993611639966 in words is "sixty-six trillion, nine hundred ninety-three billion, six hundred eleven million, six hundred thirty-nine thousand, nine hundred sixty-six".