66201864 has 64 divisors (see below), whose sum is σ = 172730880. Its totient is φ = 21120000.

The previous prime is 66201857. The next prime is 66201869. The reversal of 66201864 is 46810266.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (66201869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74704 + ... + 75584.

It is an arithmetic number, because the mean of its divisors is an integer number (2698920).

Almost surely, 2^66201864 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 66201864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86365440).

66201864 is an abundant number, since it is smaller than the sum of its proper divisors (106529016).

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

66201864 is a wasteful number, since it uses less digits than its factorization.

66201864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022 (or 1018 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 66201864 is about 8136.4527897604. The cubic root of 66201864 is about 404.5355932667.

It can be divided in two parts, 66 and 201864, that added together give a triangular number (201930 = T₆₃₅).

The spelling of 66201864 in words is "sixty-six million, two hundred one thousand, eight hundred sixty-four".