66744781178 has 8 divisors (see below), whose sum is σ = 101035678260. Its totient is φ = 33066221760.

The previous prime is 66744781177. The next prime is 66744781189. The reversal of 66744781178 is 87118744766.

66744781178 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 66738005569 + 6775609 = 258337^2 + 2603^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66744781177) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153084143 + ... + 153084578.

Almost surely, 2^66744781178 is an apocalyptic number.

66744781178 is a deficient number, since it is larger than the sum of its proper divisors (34290897082).

66744781178 is a wasteful number, since it uses less digits than its factorization.

66744781178 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306168832.

The product of its digits is 12644352, while the sum is 59.

The spelling of 66744781178 in words is "sixty-six billion, seven hundred forty-four million, seven hundred eighty-one thousand, one hundred seventy-eight".