21211221223111 has 16 divisors (see below), whose sum is σ = 22107779389696. Its totient is φ = 20328874560000.

The previous prime is 21211221223081. The next prime is 21211221223151. The reversal of 21211221223111 is 11132212211212.

It is a cyclic number.

It is not a de Polignac number, because 21211221223111 - 2¹³ = 21211221214919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211221223151) 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, 6490680 + ... + 9195181.

It is an arithmetic number, because the mean of its divisors is an integer number (1381736211856).

Almost surely, 2^{21211221223111} is an apocalyptic number.

21211221223111 is a deficient number, since it is larger than the sum of its proper divisors (896558166585).

21211221223111 is a wasteful number, since it uses less digits than its factorization.

21211221223111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15686314.

The product of its digits is 192, while the sum is 22.

Adding to 21211221223111 its reverse (11132212211212), we get a palindrome (32343433434323).

The spelling of 21211221223111 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-one million, two hundred twenty-three thousand, one hundred eleven".