21311144103 has 4 divisors (see below), whose sum is σ = 28414858808. Its totient is φ = 14207429400.

The previous prime is 21311144093. The next prime is 21311144167. The reversal of 21311144103 is 30144111312.

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

It is not a de Polignac number, because 21311144103 - 2²¹ = 21309046951 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21311144103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311144003) 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, 3551857348 + ... + 3551857353.

It is an arithmetic number, because the mean of its divisors is an integer number (7103714702).

Almost surely, 2^21311144103 is an apocalyptic number.

21311144103 is a deficient number, since it is larger than the sum of its proper divisors (7103714705).

21311144103 is an equidigital number, since it uses as much as digits as its factorization.

21311144103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7103714704.

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 21311144103 its reverse (30144111312), we get a palindrome (51455255415).

The spelling of 21311144103 in words is "twenty-one billion, three hundred eleven million, one hundred forty-four thousand, one hundred three".