21220000221 has 48 divisors (see below), whose sum is σ = 33799526208. Its totient is φ = 11800454400.

The previous prime is 21220000201. The next prime is 21220000259. The reversal of 21220000221 is 12200002212.

It is not a de Polignac number, because 21220000221 - 2¹³ = 21219992029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21220000197 and 21220000206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220000201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2533186 + ... + 2541548.

It is an arithmetic number, because the mean of its divisors is an integer number (704156796).

Almost surely, 2^21220000221 is an apocalyptic number.

21220000221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21220000221 is a deficient number, since it is larger than the sum of its proper divisors (12579525987).

21220000221 is a wasteful number, since it uses less digits than its factorization.

21220000221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8842 (or 8835 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21220000221 its reverse (12200002212), we get a palindrome (33420002433).

It can be divided in two parts, 2 and 1220000221, that multiplied together give a palindrome (2440000442).

The spelling of 21220000221 in words is "twenty-one billion, two hundred twenty million, two hundred twenty-one", and thus it is an aban number.