66493934661 has 32 divisors (see below), whose sum is σ = 112092235776. Its totient is φ = 34055784000.

The previous prime is 66493934609. The next prime is 66493934699. The reversal of 66493934661 is 16643939466.

It is not a de Polignac number, because 66493934661 - 2¹⁷ = 66493803589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66493934761) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2010730 + ... + 2043531.

It is an arithmetic number, because the mean of its divisors is an integer number (3502882368).

Almost surely, 2^66493934661 is an apocalyptic number.

It is an amenable number.

66493934661 is a deficient number, since it is larger than the sum of its proper divisors (45598301115).

66493934661 is a wasteful number, since it uses less digits than its factorization.

66493934661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4054353.

The product of its digits is 15116544, while the sum is 57.

The spelling of 66493934661 in words is "sixty-six billion, four hundred ninety-three million, nine hundred thirty-four thousand, six hundred sixty-one".