21020244143444 has 144 divisors (see below), whose sum is σ = 47575259504640. Its totient is φ = 8046459025920.

The previous prime is 21020244143441. The next prime is 21020244143473. The reversal of 21020244143444 is 44434144202012.

It is a super-2 number, since 2×21020244143444² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020244143441) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1144447949 + ... + 1144466315.

It is an arithmetic number, because the mean of its divisors is an integer number (330383746560).

Almost surely, 2^{21020244143444} 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 21020244143444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23787629752320).

21020244143444 is an abundant number, since it is smaller than the sum of its proper divisors (26555015361196).

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

21020244143444 is a wasteful number, since it uses less digits than its factorization.

21020244143444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32918 (or 32909 counting only the distinct ones).

The product of its (nonzero) digits is 98304, while the sum is 35.

Adding to 21020244143444 its reverse (44434144202012), we get a palindrome (65454388345456).

The spelling of 21020244143444 in words is "twenty-one trillion, twenty billion, two hundred forty-four million, one hundred forty-three thousand, four hundred forty-four".