21111031311103 has 4 divisors (see below), whose sum is σ = 21111053964840. Its totient is φ = 21111008657368.

The previous prime is 21111031311037. The next prime is 21111031311113. The reversal of 21111031311103 is 30111313011112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111031311103 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 (21111031311113) 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, 9866233 + ... + 11813746.

It is an arithmetic number, because the mean of its divisors is an integer number (5277763491210).

Almost surely, 2^{21111031311103} is an apocalyptic number.

21111031311103 is a deficient number, since it is larger than the sum of its proper divisors (22653737).

21111031311103 is an equidigital number, since it uses as much as digits as its factorization.

21111031311103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22653736.

The product of its (nonzero) digits is 54, while the sum is 19.

Adding to 21111031311103 its reverse (30111313011112), we get a palindrome (51222344322215).

The spelling of 21111031311103 in words is "twenty-one trillion, one hundred eleven billion, thirty-one million, three hundred eleven thousand, one hundred three".