66174993 has 6 divisors (see below), whose sum is σ = 95586114. Its totient is φ = 44116656.

The previous prime is 66174991. The next prime is 66175003. The reversal of 66174993 is 39947166.

It can be written as a sum of positive squares in only one way, i.e., 41254929 + 24920064 = 6423^2 + 4992^2 .

It is not a de Polignac number, because 66174993 - 2¹ = 66174991 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66174991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3676380 + ... + 3676397.

It is an arithmetic number, because the mean of its divisors is an integer number (15931019).

Almost surely, 2^66174993 is an apocalyptic number.

It is an amenable number.

66174993 is a deficient number, since it is larger than the sum of its proper divisors (29411121).

66174993 is a wasteful number, since it uses less digits than its factorization.

66174993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7352783 (or 7352780 counting only the distinct ones).

The product of its digits is 244944, while the sum is 45.

The square root of 66174993 is about 8134.8013497565. The cubic root of 66174993 is about 404.4808528796.

The spelling of 66174993 in words is "sixty-six million, one hundred seventy-four thousand, nine hundred ninety-three".