21202212221111 has 16 divisors (see below), whose sum is σ = 22659301174464. Its totient is φ = 19768620662784.

The previous prime is 21202212221053. The next prime is 21202212221171. The reversal of 21202212221111 is 11112221220212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202212221111 is a prime.

It is a super-3 number, since 3×21202212221111³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202212221171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1138646 + ... + 6610668.

It is an arithmetic number, because the mean of its divisors is an integer number (1416206323404).

Almost surely, 2^{21202212221111} is an apocalyptic number.

21202212221111 is a deficient number, since it is larger than the sum of its proper divisors (1457088953353).

21202212221111 is a wasteful number, since it uses less digits than its factorization.

21202212221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5474170.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21202212221111 its reverse (11112221220212), we get a palindrome (32314433441323).

The spelling of 21202212221111 in words is "twenty-one trillion, two hundred two billion, two hundred twelve million, two hundred twenty-one thousand, one hundred eleven".