20121122220 has 48 divisors (see below), whose sum is σ = 56418724320. Its totient is φ = 5358053376.

The previous prime is 20121122209. The next prime is 20121122237. The reversal of 20121122220 is 2222112102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20121122220.

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, 193957 + ... + 279036.

It is an arithmetic number, because the mean of its divisors is an integer number (1175390090).

Almost surely, 2^20121122220 is an apocalyptic number.

20121122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121122220 is an abundant number, since it is smaller than the sum of its proper divisors (36297602100).

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

20121122220 is a wasteful number, since it uses less digits than its factorization.

20121122220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473714 (or 473712 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 20121122220 its reverse (2222112102), we get a palindrome (22343234322).

The spelling of 20121122220 in words is "twenty billion, one hundred twenty-one million, one hundred twenty-two thousand, two hundred twenty".