20873758817664 has 224 divisors, whose sum is σ = 64498084768800. Its totient is φ = 6717990472704.

The previous prime is 20873758817657. The next prime is 20873758817687. The reversal of 20873758817664 is 46671885737802.

20873758817664 is a `hidden beast` number, since 2 + 0 + 8 + 7 + 37 + 588 + 1 + 7 + 6 + 6 + 4 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 20873758817592 and 20873758817601.

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 27 ways as a sum of consecutive naturals, for example, 1150824 + ... + 6562919.

Almost surely, 2^{20873758817664} is an apocalyptic number.

20873758817664 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 20873758817664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32249042384400).

20873758817664 is an abundant number, since it is smaller than the sum of its proper divisors (43624325951136).

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

20873758817664 is an frugal number, since it uses more digits than its factorization.

20873758817664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7713804 (or 7713777 counting only the distinct ones).

The product of its (nonzero) digits is 758661120, while the sum is 72.

The spelling of 20873758817664 in words is "twenty trillion, eight hundred seventy-three billion, seven hundred fifty-eight million, eight hundred seventeen thousand, six hundred sixty-four".