16638656575 has 6 divisors (see below), whose sum is σ = 20631934184. Its totient is φ = 13310925240.

The previous prime is 16638656569. The next prime is 16638656579. The reversal of 16638656575 is 57565683661.

It is a de Polignac number, because none of the positive numbers 2^k-16638656575 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 (16638656579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 332773107 + ... + 332773156.

Almost surely, 2^16638656575 is an apocalyptic number.

16638656575 is a deficient number, since it is larger than the sum of its proper divisors (3993277609).

16638656575 is an equidigital number, since it uses as much as digits as its factorization.

16638656575 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665546273 (or 665546268 counting only the distinct ones).

The product of its digits is 27216000, while the sum is 58.

The spelling of 16638656575 in words is "sixteen billion, six hundred thirty-eight million, six hundred fifty-six thousand, five hundred seventy-five".