21144404341320 has 512 divisors, whose sum is σ = 71074083225600. Its totient is φ = 4996535943168.

The previous prime is 21144404341303. The next prime is 21144404341321. The reversal of 21144404341320 is 2314340444112.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21144404341321) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6116401032 + ... + 6116404488.

It is an arithmetic number, because the mean of its divisors is an integer number (138816568800).

Almost surely, 2^{21144404341320} is an apocalyptic number.

21144404341320 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 21144404341320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35537041612800).

21144404341320 is an abundant number, since it is smaller than the sum of its proper divisors (49929678884280).

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

21144404341320 is a wasteful number, since it uses less digits than its factorization.

21144404341320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4249 (or 4245 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 33.

Adding to 21144404341320 its reverse (2314340444112), we get a palindrome (23458744785432).

The spelling of 21144404341320 in words is "twenty-one trillion, one hundred forty-four billion, four hundred four million, three hundred forty-one thousand, three hundred twenty".