20011121220 has 48 divisors (see below), whose sum is σ = 56141305920. Its totient is φ = 5325806976.

The previous prime is 20011121203. The next prime is 20011121237. The reversal of 20011121220 is 2212111002.

It is an interprime number because it is at equal distance from previous prime (20011121203) and next prime (20011121237).

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 = 20011121196 and 20011121205.

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, 297082 + ... + 358161.

It is an arithmetic number, because the mean of its divisors is an integer number (1169610540).

Almost surely, 2^20011121220 is an apocalyptic number.

20011121220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20011121220 is an abundant number, since it is smaller than the sum of its proper divisors (36130184700).

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

20011121220 is a wasteful number, since it uses less digits than its factorization.

20011121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655764 (or 655762 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 20011121220 its reverse (2212111002), we get a palindrome (22223232222).

The spelling of 20011121220 in words is "twenty billion, eleven million, one hundred twenty-one thousand, two hundred twenty".