21035442444400 has 120 divisors (see below), whose sum is σ = 51921986780160. Its totient is φ = 8185838426880.

The previous prime is 21035442444329. The next prime is 21035442444437. The reversal of 21035442444400 is 444424453012.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21035442444400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 210420 + ... + 6489619.

It is an arithmetic number, because the mean of its divisors is an integer number (432683223168).

Almost surely, 2^{21035442444400} is an apocalyptic number.

21035442444400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21035442444400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25960993390080).

21035442444400 is an abundant number, since it is smaller than the sum of its proper divisors (30886544335760).

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

21035442444400 is a wasteful number, since it uses less digits than its factorization.

21035442444400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6700271 (or 6700260 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 37.

Adding to 21035442444400 its reverse (444424453012), we get a palindrome (21479866897412).

The spelling of 21035442444400 in words is "twenty-one trillion, thirty-five billion, four hundred forty-two million, four hundred forty-four thousand, four hundred".