20915856596448 has 336 divisors, whose sum is σ = 67881955792896. Its totient is φ = 6288221963520.

The previous prime is 20915856596399. The next prime is 20915856596491. The reversal of 20915856596448 is 84469565851902.

20915856596448 is a `hidden beast` number, since 2 + 0 + 9 + 1 + 58 + 565 + 9 + 6 + 4 + 4 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

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 55 ways as a sum of consecutive naturals, for example, 32268315 + ... + 32910117.

It is an arithmetic number, because the mean of its divisors is an integer number (202029630336).

Almost surely, 2^{20915856596448} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20915856596448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33940977896448).

20915856596448 is an abundant number, since it is smaller than the sum of its proper divisors (46966099196448).

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

20915856596448 is a wasteful number, since it uses less digits than its factorization.

20915856596448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641969 (or 641946 counting only the distinct ones).

The product of its (nonzero) digits is 746496000, while the sum is 72.

The spelling of 20915856596448 in words is "twenty trillion, nine hundred fifteen billion, eight hundred fifty-six million, five hundred ninety-six thousand, four hundred forty-eight".