21231123231111 has 16 divisors (see below), whose sum is σ = 28515113961600. Its totient is φ = 14050630855008.

The previous prime is 21231123231061. The next prime is 21231123231121. The reversal of 21231123231111 is 11113232113212.

It is not a de Polignac number, because 21231123231111 - 2¹⁴ = 21231123214727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231123231121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 678420 + ... + 6551526.

It is an arithmetic number, because the mean of its divisors is an integer number (1782194622600).

Almost surely, 2^{21231123231111} is an apocalyptic number.

21231123231111 is a deficient number, since it is larger than the sum of its proper divisors (7283990730489).

21231123231111 is a wasteful number, since it uses less digits than its factorization.

21231123231111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5881918.

The product of its digits is 432, while the sum is 24.

Adding to 21231123231111 its reverse (11113232113212), we get a palindrome (32344355344323).

The spelling of 21231123231111 in words is "twenty-one trillion, two hundred thirty-one billion, one hundred twenty-three million, two hundred thirty-one thousand, one hundred eleven".