21030343420 has 96 divisors (see below), whose sum is σ = 48419320320. Its totient is φ = 7644430080.

The previous prime is 21030343409. The next prime is 21030343423. The reversal of 21030343420 is 2434303012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21030343391 and 21030343400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21030343423) 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 31 ways as a sum of consecutive naturals, for example, 987727 + ... + 1008793.

It is an arithmetic number, because the mean of its divisors is an integer number (504367920).

Almost surely, 2^21030343420 is an apocalyptic number.

21030343420 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 21030343420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24209660160).

21030343420 is an abundant number, since it is smaller than the sum of its proper divisors (27388976900).

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

21030343420 is a wasteful number, since it uses less digits than its factorization.

21030343420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21203 (or 21201 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 22.

Adding to 21030343420 its reverse (2434303012), we get a palindrome (23464646432).

The spelling of 21030343420 in words is "twenty-one billion, thirty million, three hundred forty-three thousand, four hundred twenty".