20878663680 has 1120 divisors, whose sum is σ = 91346365440. Its totient is φ = 4459069440.

The previous prime is 20878663667. The next prime is 20878663681. The reversal of 20878663680 is 8636687802.

It is a happy number.

20878663680 is a `hidden beast` number, since 208 + 78 + 6 + 6 + 368 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1120).

It is a super-3 number, since 3×20878663680³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20878663681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 673505265 + ... + 673505295.

Almost surely, 2^20878663680 is an apocalyptic number.

20878663680 is a gapful number since it is divisible by the number (20) 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 20878663680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45673182720).

20878663680 is an abundant number, since it is smaller than the sum of its proper divisors (70467701760).

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

20878663680 is an equidigital number, since it uses as much as digits as its factorization.

20878663680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 54.

The spelling of 20878663680 in words is "twenty billion, eight hundred seventy-eight million, six hundred sixty-three thousand, six hundred eighty".