21113354403421 has 16 divisors (see below), whose sum is σ = 24410376898560. Its totient is φ = 17887746165120.

The previous prime is 21113354403403. The next prime is 21113354403473. The reversal of 21113354403421 is 12430445331112.

It is a cyclic number.

It is not a de Polignac number, because 21113354403421 - 2⁹ = 21113354402909 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 (21113354406421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50081776 + ... + 50501593.

It is an arithmetic number, because the mean of its divisors is an integer number (1525648556160).

Almost surely, 2^{21113354403421} is an apocalyptic number.

It is an amenable number.

21113354403421 is a deficient number, since it is larger than the sum of its proper divisors (3297022495139).

21113354403421 is a wasteful number, since it uses less digits than its factorization.

21113354403421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100583724.

The product of its (nonzero) digits is 34560, while the sum is 34.

Adding to 21113354403421 its reverse (12430445331112), we get a palindrome (33543799734533).

The spelling of 21113354403421 in words is "twenty-one trillion, one hundred thirteen billion, three hundred fifty-four million, four hundred three thousand, four hundred twenty-one".