66569799647 has 8 divisors (see below), whose sum is σ = 71692557216. Its totient is φ = 61447328352.

The previous prime is 66569799577. The next prime is 66569799661. The reversal of 66569799647 is 74699796566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66569799647 - 2⁸ = 66569799391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66569799347) 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, 886358 + ... + 958524.

It is an arithmetic number, because the mean of its divisors is an integer number (8961569652).

Almost surely, 2^66569799647 is an apocalyptic number.

66569799647 is a deficient number, since it is larger than the sum of its proper divisors (5122757569).

66569799647 is a wasteful number, since it uses less digits than its factorization.

66569799647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143137.

The product of its digits is 925888320, while the sum is 74.

The spelling of 66569799647 in words is "sixty-six billion, five hundred sixty-nine million, seven hundred ninety-nine thousand, six hundred forty-seven".