21424011320 has 64 divisors (see below), whose sum is σ = 51304324320. Its totient is φ = 8023670784.

The previous prime is 21424011313. The next prime is 21424011353. The reversal of 21424011320 is 2311042412.

It is a super-2 number, since 2×21424011320² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21424011292 and 21424011301.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49619 + ... + 212861.

Almost surely, 2^21424011320 is an apocalyptic number.

21424011320 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 21424011320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25652162160).

21424011320 is an abundant number, since it is smaller than the sum of its proper divisors (29880313000).

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

21424011320 is a wasteful number, since it uses less digits than its factorization.

21424011320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163464 (or 163460 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21424011320 its reverse (2311042412), we get a palindrome (23735053732).

The spelling of 21424011320 in words is "twenty-one billion, four hundred twenty-four million, eleven thousand, three hundred twenty".