21123223211121 has 32 divisors (see below), whose sum is σ = 29671146086400. Its totient is φ = 13329954060480.

The previous prime is 21123223211107. The next prime is 21123223211201. The reversal of 21123223211121 is 12111232232112.

It is not a de Polignac number, because 21123223211121 - 2¹⁰ = 21123223210097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21123223211091 and 21123223211100.

It is not an unprimeable number, because it can be changed into a prime (21123223211021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 483225456 + ... + 483269166.

It is an arithmetic number, because the mean of its divisors is an integer number (927223315200).

Almost surely, 2^{21123223211121} is an apocalyptic number.

It is an amenable number.

21123223211121 is a deficient number, since it is larger than the sum of its proper divisors (8547922875279).

21123223211121 is a wasteful number, since it uses less digits than its factorization.

21123223211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50549.

The product of its digits is 576, while the sum is 24.

Adding to 21123223211121 its reverse (12111232232112), we get a palindrome (33234455443233).

The spelling of 21123223211121 in words is "twenty-one trillion, one hundred twenty-three billion, two hundred twenty-three million, two hundred eleven thousand, one hundred twenty-one".