20642442336 has 144 divisors (see below), whose sum is σ = 59816549520. Its totient is φ = 6750643200.

The previous prime is 20642442319. The next prime is 20642442343. The reversal of 20642442336 is 63324424602.

20642442336 is a `hidden beast` number, since 2 + 0 + 642 + 4 + 4 + 2 + 3 + 3 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×20642442336² (a number of 21 digits) contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20642442336.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11910526 + ... + 11912258.

It is an arithmetic number, because the mean of its divisors is an integer number (415392705).

Almost surely, 2^20642442336 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 20642442336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29908274760).

20642442336 is an abundant number, since it is smaller than the sum of its proper divisors (39174107184).

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

20642442336 is a wasteful number, since it uses less digits than its factorization.

20642442336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2509 (or 2498 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 36.

Adding to 20642442336 its reverse (63324424602), we get a palindrome (83966866938).

The spelling of 20642442336 in words is "twenty billion, six hundred forty-two million, four hundred forty-two thousand, three hundred thirty-six".