20121244420 has 12 divisors (see below), whose sum is σ = 42254613324. Its totient is φ = 8048497760.

The previous prime is 20121244379. The next prime is 20121244433. The reversal of 20121244420 is 2444212102.

It can be written as a sum of positive squares in 2 ways, for example, as 6699095104 + 13422149316 = 81848^2 + 115854^2 .

It is a super-2 number, since 2×20121244420² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20121244391 and 20121244400.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503031091 + ... + 503031130.

It is an arithmetic number, because the mean of its divisors is an integer number (3521217777).

Almost surely, 2^20121244420 is an apocalyptic number.

20121244420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121244420 is an abundant number, since it is smaller than the sum of its proper divisors (22133368904).

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

20121244420 is a wasteful number, since it uses less digits than its factorization.

20121244420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006062230 (or 1006062228 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

Adding to 20121244420 its reverse (2444212102), we get a palindrome (22565456522).

The spelling of 20121244420 in words is "twenty billion, one hundred twenty-one million, two hundred forty-four thousand, four hundred twenty".