20904205674168 has 256 divisors, whose sum is σ = 64745669952000. Its totient is φ = 6210445105152.

The previous prime is 20904205674167. The next prime is 20904205674223. The reversal of 20904205674168 is 86147650240902.

20904205674168 is a `hidden beast` number, since 2 + 0 + 9 + 0 + 420 + 56 + 7 + 4 + 168 = 666.

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 (20904205674167) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 172056930 + ... + 172178382.

It is an arithmetic number, because the mean of its divisors is an integer number (252912773250).

Almost surely, 2^{20904205674168} 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 20904205674168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32372834976000).

20904205674168 is an abundant number, since it is smaller than the sum of its proper divisors (43841464277832).

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

20904205674168 is a wasteful number, since it uses less digits than its factorization.

20904205674168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123971 (or 123961 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 20904205674168 in words is "twenty trillion, nine hundred four billion, two hundred five million, six hundred seventy-four thousand, one hundred sixty-eight".