66203664 has 80 divisors (see below), whose sum is σ = 176447040. Its totient is φ = 21381120.

The previous prime is 66203663. The next prime is 66203681. The reversal of 66203664 is 46630266.

It is not an unprimeable number, because it can be changed into a prime (66203663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 274584 + ... + 274824.

It is an arithmetic number, because the mean of its divisors is an integer number (2205588).

Almost surely, 2^66203664 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 66203664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88223520).

66203664 is an abundant number, since it is smaller than the sum of its proper divisors (110243376).

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

66203664 is a wasteful number, since it uses less digits than its factorization.

66203664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 33.

The square root of 66203664 is about 8136.5634023216. The cubic root of 66203664 is about 404.5392596160.

The spelling of 66203664 in words is "sixty-six million, two hundred three thousand, six hundred sixty-four".