20805065438976 has 1296 divisors, whose sum is σ = 76335193421760. Its totient is φ = 5401047859200.

The previous prime is 20805065438933. The next prime is 20805065438981. The reversal of 20805065438976 is 67983456050802.

It is a happy number.

20805065438976 is a `hidden beast` number, since 2 + 0 + 8 + 0 + 5 + 0 + 6 + 543 + 89 + 7 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

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 in 143 ways as a sum of consecutive naturals, for example, 34617413076 + ... + 34617413676.

Almost surely, 2^{20805065438976} is an apocalyptic number.

20805065438976 is a gapful number since it is divisible by the number (26) 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 20805065438976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38167596710880).

20805065438976 is an abundant number, since it is smaller than the sum of its proper divisors (55530127982784).

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

20805065438976 is a wasteful number, since it uses less digits than its factorization.

20805065438976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 982 (or 958 counting only the distinct ones).

The product of its (nonzero) digits is 87091200, while the sum is 63.

The spelling of 20805065438976 in words is "twenty trillion, eight hundred five billion, sixty-five million, four hundred thirty-eight thousand, nine hundred seventy-six".