66647568 has 120 divisors (see below), whose sum is σ = 193543168. Its totient is φ = 19643904.

The previous prime is 66647527. The next prime is 66647569. The reversal of 66647568 is 86574666.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (66647569) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 524721 + ... + 524847.

Almost surely, 2^66647568 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 66647568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96771584).

66647568 is an abundant number, since it is smaller than the sum of its proper divisors (126895600).

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

66647568 is a wasteful number, since it uses less digits than its factorization.

66647568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209 (or 174 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 48.

The square root of 66647568 is about 8163.7961757996. The cubic root of 66647568 is about 405.4414086906.

The spelling of 66647568 in words is "sixty-six million, six hundred forty-seven thousand, five hundred sixty-eight".