20121020320 has 96 divisors (see below), whose sum is σ = 49370504400. Its totient is φ = 7742693376.

The previous prime is 20121020317. The next prime is 20121020341. The reversal of 20121020320 is 2302012102.

It can be written as a sum of positive squares in 8 ways, for example, as 5312077456 + 14808942864 = 72884^2 + 121692^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20121020320.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 507786 + ... + 545974.

Almost surely, 2^20121020320 is an apocalyptic number.

20121020320 is a gapful number since it is divisible by the number (20) 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 20121020320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24685252200).

20121020320 is an abundant number, since it is smaller than the sum of its proper divisors (29249484080).

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

20121020320 is a wasteful number, since it uses less digits than its factorization.

20121020320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38330 (or 38322 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 20121020320 its reverse (2302012102), we get a palindrome (22423032422).

The spelling of 20121020320 in words is "twenty billion, one hundred twenty-one million, twenty thousand, three hundred twenty".