21222120202 has 16 divisors (see below), whose sum is σ = 32197198824. Its totient is φ = 10490040000.

The previous prime is 21222120191. The next prime is 21222120209. The reversal of 21222120202 is 20202122212.

It can be written as a sum of positive squares in 4 ways, for example, as 19193608681 + 2028511521 = 138541^2 + 45039^2 .

It is not an unprimeable number, because it can be changed into a prime (21222120209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54052 + ... + 212992.

Almost surely, 2^21222120202 is an apocalyptic number.

21222120202 is a deficient number, since it is larger than the sum of its proper divisors (10975078622).

21222120202 is a wasteful number, since it uses less digits than its factorization.

21222120202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159705.

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

Adding to 21222120202 its reverse (20202122212), we get a palindrome (41424242414).

The spelling of 21222120202 in words is "twenty-one billion, two hundred twenty-two million, one hundred twenty thousand, two hundred two".