20530433664 has 240 divisors, whose sum is σ = 66165276870. Its totient is φ = 6316517376.

The previous prime is 20530433663. The next prime is 20530433699. The reversal of 20530433664 is 46633403502.

20530433664 is a `hidden beast` number, since 20 + 530 + 43 + 3 + 6 + 64 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 3528360000 + 17002073664 = 59400^2 + 130392^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20530433663) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1746334 + ... + 1758050.

Almost surely, 2^20530433664 is an apocalyptic number.

20530433664 is a gapful number since it is divisible by the number (24) 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 20530433664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33082638435).

20530433664 is an abundant number, since it is smaller than the sum of its proper divisors (45634843206).

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

20530433664 is a wasteful number, since it uses less digits than its factorization.

20530433664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11769 (or 11735 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 36.

The spelling of 20530433664 in words is "twenty billion, five hundred thirty million, four hundred thirty-three thousand, six hundred sixty-four".