6609666978 has 12 divisors (see below), whose sum is σ = 14320945158. Its totient is φ = 2203222320.

The previous prime is 6609666977. The next prime is 6609667019. The reversal of 6609666978 is 8796669066.

It can be written as a sum of positive squares in only one way, i.e., 5162853609 + 1446813369 = 71853^2 + 38037^2 .

It is not an unprimeable number, because it can be changed into a prime (6609666977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 183601843 + ... + 183601878.

Almost surely, 2^6609666978 is an apocalyptic number.

6609666978 is an abundant number, since it is smaller than the sum of its proper divisors (7711278180).

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

6609666978 is a wasteful number, since it uses less digits than its factorization.

6609666978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367203729 (or 367203726 counting only the distinct ones).

The product of its (nonzero) digits is 35271936, while the sum is 63.

The square root of 6609666978 is about 81299.8584131608. The cubic root of 6609666978 is about 1876.6928217025.

The spelling of 6609666978 in words is "six billion, six hundred nine million, six hundred sixty-six thousand, nine hundred seventy-eight".