20859904166400 has 2880 divisors, whose sum is σ = 87982598753280. Its totient is φ = 4830658560000.

The previous prime is 20859904166273. The next prime is 20859904166447. The reversal of 20859904166400 is 466140995802.

20859904166400 is a `hidden beast` number, since 2 + 0 + 8 + 59 + 90 + 41 + 66 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (2880).

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

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 287 ways as a sum of consecutive naturals, for example, 74234534260 + ... + 74234534540.

It is an arithmetic number, because the mean of its divisors is an integer number (30549513456).

Almost surely, 2^{20859904166400} is an apocalyptic number.

20859904166400 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 20859904166400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43991299376640).

20859904166400 is an abundant number, since it is smaller than the sum of its proper divisors (67122694586880).

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

20859904166400 is a wasteful number, since it uses less digits than its factorization.

20859904166400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416 (or 376 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 20859904166400 in words is "twenty trillion, eight hundred fifty-nine billion, nine hundred four million, one hundred sixty-six thousand, four hundred".