221212220020 has 48 divisors (see below), whose sum is σ = 506907471168. Its totient is φ = 80420111360.

The previous prime is 221212220011. The next prime is 221212220029. The reversal of 221212220020 is 20022212122.

It is an interprime number because it is at equal distance from previous prime (221212220011) and next prime (221212220029).

It is a junction number, because it is equal to n+sod(n) for n = 221212219976 and 221212220003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212220029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 740964 + ... + 995716.

It is an arithmetic number, because the mean of its divisors is an integer number (10560572316).

Almost surely, 2^221212220020 is an apocalyptic number.

221212220020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221212220020 is an abundant number, since it is smaller than the sum of its proper divisors (285695251148).

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

221212220020 is a wasteful number, since it uses less digits than its factorization.

221212220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258720 (or 258718 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 221212220020 its reverse (20022212122), we get a palindrome (241234432142).

The spelling of 221212220020 in words is "two hundred twenty-one billion, two hundred twelve million, two hundred twenty thousand, twenty".