21123002312111 has 24 divisors (see below), whose sum is σ = 24711136128000. Its totient is φ = 18002673635184.

The previous prime is 21123002312081. The next prime is 21123002312147. The reversal of 21123002312111 is 11121320032112.

It is a de Polignac number, because none of the positive numbers 2^k-21123002312111 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123002312011) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 103738160 + ... + 103941578.

It is an arithmetic number, because the mean of its divisors is an integer number (1029630672000).

Almost surely, 2^{21123002312111} is an apocalyptic number.

21123002312111 is a deficient number, since it is larger than the sum of its proper divisors (3588133815889).

21123002312111 is a wasteful number, since it uses less digits than its factorization.

21123002312111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215451 (or 215444 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 21123002312111 its reverse (11121320032112), we get a palindrome (32244322344223).

The spelling of 21123002312111 in words is "twenty-one trillion, one hundred twenty-three billion, two million, three hundred twelve thousand, one hundred eleven".