21402443330424 has 256 divisors, whose sum is σ = 66271059792000. Its totient is φ = 6354549411840.

The previous prime is 21402443330357. The next prime is 21402443330479. The reversal of 21402443330424 is 42403334420412.

21402443330424 is a `hidden beast` number, since 2 + 1 + 40 + 244 + 3 + 330 + 42 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 140068114 + ... + 140220830.

Almost surely, 2^{21402443330424} is an apocalyptic number.

21402443330424 is a gapful number since it is divisible by the number (24) 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 21402443330424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33135529896000).

21402443330424 is an abundant number, since it is smaller than the sum of its proper divisors (44868616461576).

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

21402443330424 is a wasteful number, since it uses less digits than its factorization.

21402443330424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154495 (or 154485 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 36.

Adding to 21402443330424 its reverse (42403334420412), we get a palindrome (63805777750836).

The spelling of 21402443330424 in words is "twenty-one trillion, four hundred two billion, four hundred forty-three million, three hundred thirty thousand, four hundred twenty-four".