21442401240 has 384 divisors, whose sum is σ = 74269440000. Its totient is φ = 4922007552.

The previous prime is 21442401187. The next prime is 21442401247. The reversal of 21442401240 is 4210424412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21442401240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442401247) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 89717041 + ... + 89717279.

It is an arithmetic number, because the mean of its divisors is an integer number (193410000).

Almost surely, 2^21442401240 is an apocalyptic number.

21442401240 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 21442401240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37134720000).

21442401240 is an abundant number, since it is smaller than the sum of its proper divisors (52827038760).

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

21442401240 is a wasteful number, since it uses less digits than its factorization.

21442401240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499 (or 478 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

Adding to 21442401240 its reverse (4210424412), we get a palindrome (25652825652).

The spelling of 21442401240 in words is "twenty-one billion, four hundred forty-two million, four hundred one thousand, two hundred forty".