66544860 has 96 divisors (see below), whose sum is σ = 191923200. Its totient is φ = 17222400.

The previous prime is 66544847. The next prime is 66544867. The reversal of 66544860 is 6844566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66544867) 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 31 ways as a sum of consecutive naturals, for example, 478671 + ... + 478809.

It is an arithmetic number, because the mean of its divisors is an integer number (1999200).

Almost surely, 2^66544860 is an apocalyptic number.

66544860 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66544860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95961600).

66544860 is an abundant number, since it is smaller than the sum of its proper divisors (125378340).

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

66544860 is a wasteful number, since it uses less digits than its factorization.

66544860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331 (or 329 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 66544860 is about 8157.5032945136. The cubic root of 66544860 is about 405.2330315670.

The spelling of 66544860 in words is "sixty-six million, five hundred forty-four thousand, eight hundred sixty".