20821818494880 has 1152 divisors, whose sum is σ = 82566559595520. Its totient is φ = 4732665200640.

The previous prime is 20821818494783. The next prime is 20821818494891. The reversal of 20821818494880 is 8849481812802.

20821818494880 is a `hidden beast` number, since 20 + 82 + 1 + 8 + 18 + 49 + 488 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 4097973940 + ... + 4097979020.

It is an arithmetic number, because the mean of its divisors is an integer number (71672360760).

Almost surely, 2^{20821818494880} is an apocalyptic number.

20821818494880 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 20821818494880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41283279797760).

20821818494880 is an abundant number, since it is smaller than the sum of its proper divisors (61744741100640).

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

20821818494880 is a wasteful number, since it uses less digits than its factorization.

20821818494880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5374 (or 5363 counting only the distinct ones).

The product of its (nonzero) digits is 18874368, while the sum is 63.

The spelling of 20821818494880 in words is "twenty trillion, eight hundred twenty-one billion, eight hundred eighteen million, four hundred ninety-four thousand, eight hundred eighty".