21221220111202 has 16 divisors (see below), whose sum is σ = 32353890060024. Its totient is φ = 10436592528000.

The previous prime is 21221220111187. The next prime is 21221220111233. The reversal of 21221220111202 is 20211102212212.

It can be written as a sum of positive squares in 4 ways, for example, as 1333999590121 + 19887220521081 = 1154989^2 + 4459509^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21221220111202.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19623052 + ... + 20676232.

Almost surely, 2^{21221220111202} is an apocalyptic number.

21221220111202 is a deficient number, since it is larger than the sum of its proper divisors (11132669948822).

21221220111202 is a wasteful number, since it uses less digits than its factorization.

21221220111202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1218405.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21221220111202 its reverse (20211102212212), we get a palindrome (41432322323414).

The spelling of 21221220111202 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty million, one hundred eleven thousand, two hundred two".