66639600672 has 48 divisors (see below), whose sum is σ = 174976925760. Its totient is φ = 22207108352.

The previous prime is 66639600661. The next prime is 66639600679. The reversal of 66639600672 is 27600693666.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (66639600679) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 263698 + ... + 450350.

It is an arithmetic number, because the mean of its divisors is an integer number (3645352620).

Almost surely, 2^66639600672 is an apocalyptic number.

It is an amenable number.

66639600672 is an abundant number, since it is smaller than the sum of its proper divisors (108337325088).

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

66639600672 is a wasteful number, since it uses less digits than its factorization.

66639600672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190385 (or 190377 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 51.

The spelling of 66639600672 in words is "sixty-six billion, six hundred thirty-nine million, six hundred thousand, six hundred seventy-two".