20945479680 has 576 divisors, whose sum is σ = 79686406800. Its totient is φ = 5064622080.

The previous prime is 20945479669. The next prime is 20945479721. The reversal of 20945479680 is 8697454902.

20945479680 is a `hidden beast` number, since 2 + 0 + 9 + 4 + 547 + 96 + 8 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 10413794304 + 10531685376 = 102048^2 + 102624^2 .

It is a tau number, because it is divible by the number of its divisors (576).

It is a super-5 number, since 5×20945479680⁵ (a number of 53 digits) contains 55555 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 45434650 + ... + 45435110.

Almost surely, 2^20945479680 is an apocalyptic number.

20945479680 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 20945479680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39843203400).

20945479680 is an abundant number, since it is smaller than the sum of its proper divisors (58740927120).

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

20945479680 is a wasteful number, since it uses less digits than its factorization.

20945479680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 20945479680 in words is "twenty billion, nine hundred forty-five million, four hundred seventy-nine thousand, six hundred eighty".