20717910528 has 160 divisors (see below), whose sum is σ = 63879720960. Its totient is φ = 5844234240.

The previous prime is 20717910511. The next prime is 20717910553. The reversal of 20717910528 is 82501971702.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 20717910528.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 837213 + ... + 861603.

It is an arithmetic number, because the mean of its divisors is an integer number (399248256).

Almost surely, 2^20717910528 is an apocalyptic number.

20717910528 is a gapful number since it is divisible by the number (28) 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 20717910528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31939860480).

20717910528 is an abundant number, since it is smaller than the sum of its proper divisors (43161810432).

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

20717910528 is an equidigital number, since it uses as much as digits as its factorization.

20717910528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24498 (or 24482 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 42.

The spelling of 20717910528 in words is "twenty billion, seven hundred seventeen million, nine hundred ten thousand, five hundred twenty-eight".