20804375520 has 144 divisors (see below), whose sum is σ = 71081442432. Its totient is φ = 5541073920.

The previous prime is 20804375507. The next prime is 20804375521. The reversal of 20804375520 is 2557340802.

20804375520 is a `hidden beast` number, since 20 + 8 + 0 + 43 + 75 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20804375521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1234350 + ... + 1251090.

It is an arithmetic number, because the mean of its divisors is an integer number (493621128).

Almost surely, 2^20804375520 is an apocalyptic number.

20804375520 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 20804375520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35540721216).

20804375520 is an abundant number, since it is smaller than the sum of its proper divisors (50277066912).

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

20804375520 is a wasteful number, since it uses less digits than its factorization.

20804375520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17625 (or 17614 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The spelling of 20804375520 in words is "twenty billion, eight hundred four million, three hundred seventy-five thousand, five hundred twenty".