20681316668664 has 144 divisors (see below), whose sum is σ = 58706845680600. Its totient is φ = 6829342590528.

The previous prime is 20681316668651. The next prime is 20681316668731. The reversal of 20681316668664 is 46686661318602.

20681316668664 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 3775002 + ... + 7457430.

Almost surely, 2^{20681316668664} is an apocalyptic number.

20681316668664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20681316668664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29353422840300).

20681316668664 is an abundant number, since it is smaller than the sum of its proper divisors (38025529011936).

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

20681316668664 is an equidigital number, since it uses as much as digits as its factorization.

20681316668664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3682566 (or 3682541 counting only the distinct ones).

The product of its (nonzero) digits is 71663616, while the sum is 63.

The spelling of 20681316668664 in words is "twenty trillion, six hundred eighty-one billion, three hundred sixteen million, six hundred sixty-eight thousand, six hundred sixty-four".