21100243080444 has 96 divisors (see below), whose sum is σ = 55172994573312. Its totient is φ = 6219885600000.

The previous prime is 21100243080437. The next prime is 21100243080493. The reversal of 21100243080444 is 44408034200112.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22749214 + ... + 23658554.

It is an arithmetic number, because the mean of its divisors is an integer number (574718693472).

Almost surely, 2^{21100243080444} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100243080444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27586497286656).

21100243080444 is an abundant number, since it is smaller than the sum of its proper divisors (34072751492868).

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

21100243080444 is a wasteful number, since it uses less digits than its factorization.

21100243080444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 914147 (or 914145 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 33.

Adding to 21100243080444 its reverse (44408034200112), we get a palindrome (65508277280556).

The spelling of 21100243080444 in words is "twenty-one trillion, one hundred billion, two hundred forty-three million, eighty thousand, four hundred forty-four".