66172100549994 has 24 divisors (see below), whose sum is σ = 143373045749700. Its totient is φ = 22057342046208.

The previous prime is 66172100549921. The next prime is 66172100549999. The reversal of 66172100549994 is 49994500127166.

66172100549994 is a `hidden beast` number, since 6 + 6 + 1 + 72 + 10 + 0 + 549 + 9 + 9 + 4 = 666.

66172100549994 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 65036757024369 + 1135343525625 = 8064537^2 + 1065525^2 .

It is not an unprimeable number, because it can be changed into a prime (66172100549999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21887724 + ... + 24726840.

Almost surely, 2^{66172100549994} is an apocalyptic number.

66172100549994 is an abundant number, since it is smaller than the sum of its proper divisors (77200945199706).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66172100549994 is a wasteful number, since it uses less digits than its factorization.

66172100549994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4133974 (or 4133971 counting only the distinct ones).

The product of its (nonzero) digits is 29393280, while the sum is 63.

The spelling of 66172100549994 in words is "sixty-six trillion, one hundred seventy-two billion, one hundred million, five hundred forty-nine thousand, nine hundred ninety-four".