21111123344 has 40 divisors (see below), whose sum is σ = 42692571072. Its totient is φ = 10093930880.

The previous prime is 21111123281. The next prime is 21111123377. The reversal of 21111123344 is 44332111112.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2410814 + ... + 2419554.

Almost surely, 2^21111123344 is an apocalyptic number.

It is an amenable number.

21111123344 is an abundant number, since it is smaller than the sum of its proper divisors (21581447728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21111123344 is a wasteful number, since it uses less digits than its factorization.

21111123344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15335 (or 15329 counting only the distinct ones).

The product of its digits is 576, while the sum is 23.

Adding to 21111123344 its reverse (44332111112), we get a palindrome (65443234456).

The spelling of 21111123344 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-three thousand, three hundred forty-four".