66806196640 has 96 divisors (see below), whose sum is σ = 162931196736. Its totient is φ = 25869742080.

The previous prime is 66806196623. The next prime is 66806196659. The reversal of 66806196640 is 4669160866.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 734475 + ... + 820405.

It is an arithmetic number, because the mean of its divisors is an integer number (1697199966).

Almost surely, 2^66806196640 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 66806196640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81465598368).

66806196640 is an abundant number, since it is smaller than the sum of its proper divisors (96125000096).

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

66806196640 is a wasteful number, since it uses less digits than its factorization.

66806196640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86102 (or 86094 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 52.

The spelling of 66806196640 in words is "sixty-six billion, eight hundred six million, one hundred ninety-six thousand, six hundred forty".