66684456 has 96 divisors (see below), whose sum is σ = 189189000. Its totient is φ = 21192192.

The previous prime is 66684377. The next prime is 66684461. The reversal of 66684456 is 65448666.

66684456 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 4 ways, for example, as 66683556 + 900 = 8166^2 + 30^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 227446 + ... + 227738.

Almost surely, 2^66684456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66684456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94594500).

66684456 is an abundant number, since it is smaller than the sum of its proper divisors (122504544).

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

66684456 is a wasteful number, since it uses less digits than its factorization.

66684456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443 (or 436 counting only the distinct ones).

The product of its digits is 829440, while the sum is 45.

The square root of 66684456 is about 8166.0551063534. The cubic root of 66684456 is about 405.5161959370.

The spelling of 66684456 in words is "sixty-six million, six hundred eighty-four thousand, four hundred fifty-six".