21134344423 has 4 divisors (see below), whose sum is σ = 22246678360. Its totient is φ = 20022010488.

The previous prime is 21134344421. The next prime is 21134344513. The reversal of 21134344423 is 32444343112.

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

It is a cyclic number.

It is not a de Polignac number, because 21134344423 - 2¹ = 21134344421 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 (21134344421) 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, 556166940 + ... + 556166977.

It is an arithmetic number, because the mean of its divisors is an integer number (5561669590).

Almost surely, 2^21134344423 is an apocalyptic number.

21134344423 is a deficient number, since it is larger than the sum of its proper divisors (1112333937).

21134344423 is a wasteful number, since it uses less digits than its factorization.

21134344423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112333936.

The product of its digits is 27648, while the sum is 31.

Adding to 21134344423 its reverse (32444343112), we get a palindrome (53578687535).

The spelling of 21134344423 in words is "twenty-one billion, one hundred thirty-four million, three hundred forty-four thousand, four hundred twenty-three".