20011212220 has 12 divisors (see below), whose sum is σ = 42023545704. Its totient is φ = 8004484880.

The previous prime is 20011212197. The next prime is 20011212241. The reversal of 20011212220 is 2221211002.

It is a happy number.

It is a super-2 number, since 2×20011212220² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20011212220.

It is a congruent number.

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, 500280286 + ... + 500280325.

It is an arithmetic number, because the mean of its divisors is an integer number (3501962142).

Almost surely, 2^20011212220 is an apocalyptic number.

20011212220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20011212220 is an abundant number, since it is smaller than the sum of its proper divisors (22012333484).

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

20011212220 is a wasteful number, since it uses less digits than its factorization.

20011212220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000560620 (or 1000560618 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20011212220 its reverse (2221211002), we get a palindrome (22232423222).

The spelling of 20011212220 in words is "twenty billion, eleven million, two hundred twelve thousand, two hundred twenty".