21113113100421 has 4 divisors (see below), whose sum is σ = 28150817467232. Its totient is φ = 14075408733612.

The previous prime is 21113113100413. The next prime is 21113113100447. The reversal of 21113113100421 is 12400131131112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21113113100421 - 2³ = 21113113100413 is a prime.

It is a super-3 number, since 3×21113113100421³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113113600421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3518852183401 + ... + 3518852183406.

It is an arithmetic number, because the mean of its divisors is an integer number (7037704366808).

Almost surely, 2^{21113113100421} is an apocalyptic number.

It is an amenable number.

21113113100421 is a deficient number, since it is larger than the sum of its proper divisors (7037704366811).

21113113100421 is an equidigital number, since it uses as much as digits as its factorization.

21113113100421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7037704366810.

The product of its (nonzero) digits is 144, while the sum is 21.

Adding to 21113113100421 its reverse (12400131131112), we get a palindrome (33513244231533).

The spelling of 21113113100421 in words is "twenty-one trillion, one hundred thirteen billion, one hundred thirteen million, one hundred thousand, four hundred twenty-one".