21440424330 has 128 divisors (see below), whose sum is σ = 61622346240. Its totient is φ = 5273372160.

The previous prime is 21440424319. The next prime is 21440424331. The reversal of 21440424330 is 3342404412.

It is a happy number.

21440424330 is a `hidden beast` number, since 2 + 14 + 404 + 243 + 3 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21440424294 and 21440424303.

It is not an unprimeable number, because it can be changed into a prime (21440424331) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8503470 + ... + 8505990.

It is an arithmetic number, because the mean of its divisors is an integer number (481424580).

Almost surely, 2^21440424330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21440424330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30811173120).

21440424330 is an abundant number, since it is smaller than the sum of its proper divisors (40181921910).

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

21440424330 is a wasteful number, since it uses less digits than its factorization.

21440424330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4973 (or 4967 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21440424330 its reverse (3342404412), we get a palindrome (24782828742).

The spelling of 21440424330 in words is "twenty-one billion, four hundred forty million, four hundred twenty-four thousand, three hundred thirty".