20517120000 has 720 divisors, whose sum is σ = 80325865620. Its totient is φ = 5013504000.

The previous prime is 20517119983. The next prime is 20517120049. The reversal of 20517120000 is 2171502.

It can be written as a sum of positive squares in 10 ways, for example, as 3646227456 + 16870892544 = 60384^2 + 129888^2 .

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (18).

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 59 ways as a sum of consecutive naturals, for example, 149759932 + ... + 149760068.

Almost surely, 2^20517120000 is an apocalyptic number.

20517120000 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 20517120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40162932810).

20517120000 is an abundant number, since it is smaller than the sum of its proper divisors (59808745620).

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

20517120000 is a wasteful number, since it uses less digits than its factorization.

20517120000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

Adding to 20517120000 its reverse (2171502), we get a palindrome (20519291502).

The spelling of 20517120000 in words is "twenty billion, five hundred seventeen million, one hundred twenty thousand".