20239646544 has 240 divisors, whose sum is σ = 63284282880. Its totient is φ = 5996436480.

The previous prime is 20239646543. The next prime is 20239646549. The reversal of 20239646544 is 44564693202.

20239646544 is a `hidden beast` number, since 20 + 23 + 9 + 64 + 6 + 544 = 666.

It is a super-2 number, since 2×20239646544² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20239646544.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20239646543) 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 47 ways as a sum of consecutive naturals, for example, 13288567 + ... + 13290089.

It is an arithmetic number, because the mean of its divisors is an integer number (263684512).

Almost surely, 2^20239646544 is an apocalyptic number.

20239646544 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 20239646544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31642141440).

20239646544 is an abundant number, since it is smaller than the sum of its proper divisors (43044636336).

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

20239646544 is a wasteful number, since it uses less digits than its factorization.

20239646544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1810 (or 1801 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 45.

The spelling of 20239646544 in words is "twenty billion, two hundred thirty-nine million, six hundred forty-six thousand, five hundred forty-four".