66557608 has 48 divisors (see below), whose sum is σ = 142300800. Its totient is φ = 29090880.

The previous prime is 66557597. The next prime is 66557609. The reversal of 66557608 is 80675566.

It is not an unprimeable number, because it can be changed into a prime (66557609) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24393 + ... + 26983.

It is an arithmetic number, because the mean of its divisors is an integer number (2964600).

Almost surely, 2^66557608 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 66557608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71150400).

66557608 is an abundant number, since it is smaller than the sum of its proper divisors (75743192).

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

66557608 is a wasteful number, since it uses less digits than its factorization.

66557608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2642 (or 2625 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 43.

The square root of 66557608 is about 8158.2846236203. The cubic root of 66557608 is about 405.2589067478.

The spelling of 66557608 in words is "sixty-six million, five hundred fifty-seven thousand, six hundred eight".