20968715520 has 108 divisors (see below), whose sum is σ = 72549611316. Its totient is φ = 5591654400.

The previous prime is 20968715507. The next prime is 20968715527. The reversal of 20968715520 is 2551786902.

20968715520 is a `hidden beast` number, since 2 + 0 + 96 + 8 + 7 + 1 + 552 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16523559936 + 4445155584 = 128544^2 + 66672^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20968715527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 898581 + ... + 921620.

Almost surely, 2^20968715520 is an apocalyptic number.

20968715520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20968715520 is an abundant number, since it is smaller than the sum of its proper divisors (51580895796).

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

20968715520 is a wasteful number, since it uses less digits than its factorization.

20968715520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1820228 (or 1820211 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The spelling of 20968715520 in words is "twenty billion, nine hundred sixty-eight million, seven hundred fifteen thousand, five hundred twenty".