20847443904 has 448 divisors, whose sum is σ = 73288550400. Its totient is φ = 5685313536.

The previous prime is 20847443843. The next prime is 20847443923. The reversal of 20847443904 is 40934474802.

20847443904 is a `hidden beast` number, since 208 + 4 + 7 + 4 + 439 + 0 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×20847443904² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20847443904.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 36130464 + ... + 36131040.

Almost surely, 2^20847443904 is an apocalyptic number.

20847443904 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 20847443904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36644275200).

20847443904 is an abundant number, since it is smaller than the sum of its proper divisors (52441106496).

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

20847443904 is a wasteful number, since it uses less digits than its factorization.

20847443904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737 (or 721 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The spelling of 20847443904 in words is "twenty billion, eight hundred forty-seven million, four hundred forty-three thousand, nine hundred four".