21434120344 has 64 divisors (see below), whose sum is σ = 49550941440. Its totient is φ = 8464417920.

The previous prime is 21434120339. The next prime is 21434120363. The reversal of 21434120344 is 44302143412.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 389907 + ... + 441469.

It is an arithmetic number, because the mean of its divisors is an integer number (774233460).

Almost surely, 2^21434120344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21434120344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24775470720).

21434120344 is an abundant number, since it is smaller than the sum of its proper divisors (28116821096).

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

21434120344 is a wasteful number, since it uses less digits than its factorization.

21434120344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52160 (or 52156 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 21434120344 its reverse (44302143412), we get a palindrome (65736263756).

It can be divided in two parts, 21434 and 120344, that added together give a triangular number (141778 = T₅₃₂).

The spelling of 21434120344 in words is "twenty-one billion, four hundred thirty-four million, one hundred twenty thousand, three hundred forty-four".