20121220020 has 192 divisors, whose sum is σ = 64952616960. Its totient is φ = 4602816000.

The previous prime is 20121219991. The next prime is 20121220027. The reversal of 20121220020 is 2002212102.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 20121219978 and 20121220005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121220027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3294970 + ... + 3301070.

It is an arithmetic number, because the mean of its divisors is an integer number (338294880).

Almost surely, 2^20121220020 is an apocalyptic number.

20121220020 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 20121220020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32476308480).

20121220020 is an abundant number, since it is smaller than the sum of its proper divisors (44831396940).

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

20121220020 is a wasteful number, since it uses less digits than its factorization.

20121220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6406 (or 6404 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 20121220020 its reverse (2002212102), we get a palindrome (22123432122).

The spelling of 20121220020 in words is "twenty billion, one hundred twenty-one million, two hundred twenty thousand, twenty".