20663655664 has 10 divisors (see below), whose sum is σ = 40035832880. Its totient is φ = 10331827824.

The previous prime is 20663655631. The next prime is 20663655667. The reversal of 20663655664 is 46655636602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20663655667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645739224 + ... + 645739255.

It is an arithmetic number, because the mean of its divisors is an integer number (4003583288).

Almost surely, 2^20663655664 is an apocalyptic number.

It is an amenable number.

20663655664 is a deficient number, since it is larger than the sum of its proper divisors (19372177216).

20663655664 is a wasteful number, since it uses less digits than its factorization.

20663655664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291478487 (or 1291478481 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 49.

The spelling of 20663655664 in words is "twenty billion, six hundred sixty-three million, six hundred fifty-five thousand, six hundred sixty-four".