20517660560 has 40 divisors (see below), whose sum is σ = 47758118136. Its totient is φ = 8197678080.

The previous prime is 20517660529. The next prime is 20517660599. The reversal of 20517660560 is 6506671502.

It can be written as a sum of positive squares in 4 ways, for example, as 11570014096 + 8947646464 = 107564^2 + 94592^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76061 + ... + 216380.

Almost surely, 2^20517660560 is an apocalyptic number.

20517660560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20517660560 is an abundant number, since it is smaller than the sum of its proper divisors (27240457576).

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

20517660560 is a wasteful number, since it uses less digits than its factorization.

20517660560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293331 (or 293325 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 20517660560 in words is "twenty billion, five hundred seventeen million, six hundred sixty thousand, five hundred sixty".