20817447552 has 512 divisors, whose sum is σ = 69938380800. Its totient is φ = 6041088000.

The previous prime is 20817447481. The next prime is 20817447569. The reversal of 20817447552 is 25574471802.

20817447552 is a `hidden beast` number, since 2 + 0 + 8 + 174 + 475 + 5 + 2 = 666.

It is a super-2 number, since 2×20817447552² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20817447498 and 20817447507.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 108991777 + ... + 108991967.

It is an arithmetic number, because the mean of its divisors is an integer number (136598400).

Almost surely, 2^20817447552 is an apocalyptic number.

20817447552 is a gapful number since it is divisible by the number (22) 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 20817447552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34969190400).

20817447552 is an abundant number, since it is smaller than the sum of its proper divisors (49120933248).

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

20817447552 is a wasteful number, since it uses less digits than its factorization.

20817447552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333 (or 315 counting only the distinct ones).

The product of its (nonzero) digits is 627200, while the sum is 45.

The spelling of 20817447552 in words is "twenty billion, eight hundred seventeen million, four hundred forty-seven thousand, five hundred fifty-two".