21888111105 has 96 divisors (see below), whose sum is σ = 44869593600. Its totient is φ = 9864570240.

The previous prime is 21888111083. The next prime is 21888111107. The reversal of 21888111105 is 50111188812.

It is a happy number.

It is not a de Polignac number, because 21888111105 - 2¹¹ = 21888109057 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21888111105.

It is not an unprimeable number, because it can be changed into a prime (21888111107) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1085899 + ... + 1105871.

It is an arithmetic number, because the mean of its divisors is an integer number (467391600).

Almost surely, 2^21888111105 is an apocalyptic number.

It is an amenable number.

21888111105 is an abundant number, since it is smaller than the sum of its proper divisors (22981482495).

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

21888111105 is a wasteful number, since it uses less digits than its factorization.

21888111105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20076 (or 20059 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 36.

Adding to 21888111105 its reverse (50111188812), we get a palindrome (71999299917).

The spelling of 21888111105 in words is "twenty-one billion, eight hundred eighty-eight million, one hundred eleven thousand, one hundred five".