20121220224 has 192 divisors, whose sum is σ = 66442783680. Its totient is φ = 5725440000.

The previous prime is 20121220187. The next prime is 20121220241. The reversal of 20121220224 is 42202212102.

20121220224 is a `hidden beast` number, since 201 + 21 + 220 + 224 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×20121220224² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20121220197 and 20121220206.

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, 2019094 + ... + 2029034.

It is an arithmetic number, because the mean of its divisors is an integer number (346056165).

Almost surely, 2^20121220224 is an apocalyptic number.

20121220224 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 20121220224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33221391840).

20121220224 is an abundant number, since it is smaller than the sum of its proper divisors (46321563456).

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

20121220224 is a wasteful number, since it uses less digits than its factorization.

20121220224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10219 (or 10204 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 20121220224 its reverse (42202212102), we get a palindrome (62323432326).

The spelling of 20121220224 in words is "twenty billion, one hundred twenty-one million, two hundred twenty thousand, two hundred twenty-four".