21113423321 has 16 divisors (see below), whose sum is σ = 22359953664. Its totient is φ = 19894938624.

The previous prime is 21113423297. The next prime is 21113423329. The reversal of 21113423321 is 12332431112.

It is a cyclic number.

It is not a de Polignac number, because 21113423321 - 2³⁴ = 3933554137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21113423329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1482185 + ... + 1496361.

It is an arithmetic number, because the mean of its divisors is an integer number (1397497104).

Almost surely, 2^21113423321 is an apocalyptic number.

It is an amenable number.

21113423321 is a deficient number, since it is larger than the sum of its proper divisors (1246530343).

21113423321 is a wasteful number, since it uses less digits than its factorization.

21113423321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15160.

The product of its digits is 864, while the sum is 23.

Adding to 21113423321 its reverse (12332431112), we get a palindrome (33445854433).

The spelling of 21113423321 in words is "twenty-one billion, one hundred thirteen million, four hundred twenty-three thousand, three hundred twenty-one".