20663859456 has 360 divisors, whose sum is σ = 66088929984. Its totient is φ = 6404935680.

The previous prime is 20663859421. The next prime is 20663859521. The reversal of 20663859456 is 65495836602.

20663859456 is a `hidden beast` number, since 206 + 6 + 385 + 9 + 4 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 17645751 + ... + 17646921.

Almost surely, 2^20663859456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20663859456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33044464992).

20663859456 is an abundant number, since it is smaller than the sum of its proper divisors (45425070528).

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

20663859456 is a wasteful number, since it uses less digits than its factorization.

20663859456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1259 (or 1236 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 54.

The spelling of 20663859456 in words is "twenty billion, six hundred sixty-three million, eight hundred fifty-nine thousand, four hundred fifty-six".