201220021220 has 24 divisors (see below), whose sum is σ = 422722642104. Its totient is φ = 80457418496.

The previous prime is 201220021213. The next prime is 201220021243. The reversal of 201220021220 is 22120022102.

It can be written as a sum of positive squares in 4 ways, for example, as 1868487076 + 199351534144 = 43226^2 + 446488^2 .

It is a junction number, because it is equal to n+sod(n) for n = 201220021195 and 201220021204.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1857899 + ... + 1963218.

It is an arithmetic number, because the mean of its divisors is an integer number (17613443421).

Almost surely, 2^201220021220 is an apocalyptic number.

201220021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201220021220 is an abundant number, since it is smaller than the sum of its proper divisors (221502620884).

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

201220021220 is a wasteful number, since it uses less digits than its factorization.

201220021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3823759 (or 3823757 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 201220021220 its reverse (22120022102), we get a palindrome (223340043322).

The spelling of 201220021220 in words is "two hundred one billion, two hundred twenty million, twenty-one thousand, two hundred twenty".