20665424052 has 180 divisors, whose sum is σ = 67678467780. Its totient is φ = 5450167296.

The previous prime is 20665424027. The next prime is 20665424057. The reversal of 20665424052 is 25042456602.

20665424052 is a `hidden beast` number, since 2 + 0 + 66 + 542 + 4 + 0 + 52 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3953139876 + 16712284176 = 62874^2 + 129276^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 20665423998 and 20665424016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20665424057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 156324 + ... + 256452.

Almost surely, 2^20665424052 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 20665424052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33839233890).

20665424052 is an abundant number, since it is smaller than the sum of its proper divisors (47013043728).

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

20665424052 is a wasteful number, since it uses less digits than its factorization.

20665424052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100172 (or 100154 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 36.

The spelling of 20665424052 in words is "twenty billion, six hundred sixty-five million, four hundred twenty-four thousand, fifty-two".