20508694560 has 168 divisors, whose sum is σ = 72644867820. Its totient is φ = 5468954112.

The previous prime is 20508694559. The next prime is 20508694561. The reversal of 20508694560 is 6549680502.

20508694560 is a `hidden beast` number, since 2 + 0 + 5 + 0 + 86 + 9 + 4 + 560 = 666.

It is an interprime number because it is at equal distance from previous prime (20508694559) and next prime (20508694561).

It can be written as a sum of positive squares in 2 ways, for example, as 16489641744 + 4019052816 = 128412^2 + 63396^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (20508694561) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 28726 + ... + 204554.

Almost surely, 2^20508694560 is an apocalyptic number.

20508694560 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 20508694560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36322433910).

20508694560 is an abundant number, since it is smaller than the sum of its proper divisors (52136173260).

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

20508694560 is an equidigital number, since it uses as much as digits as its factorization.

20508694560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175862 (or 175839 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 20508694560 in words is "twenty billion, five hundred eight million, six hundred ninety-four thousand, five hundred sixty".