21325434452 has 72 divisors (see below), whose sum is σ = 43711232040. Its totient is φ = 9076838400.

The previous prime is 21325434439. The next prime is 21325434463. The reversal of 21325434452 is 25443452312.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1097199376 + 20228235076 = 33124^2 + 142226^2 .

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 31686788 + ... + 31687460.

It is an arithmetic number, because the mean of its divisors is an integer number (607100445).

Almost surely, 2^21325434452 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 21325434452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21855616020).

21325434452 is an abundant number, since it is smaller than the sum of its proper divisors (22385797588).

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

21325434452 is a wasteful number, since it uses less digits than its factorization.

21325434452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1561 (or 1552 counting only the distinct ones).

The product of its digits is 115200, while the sum is 35.

Adding to 21325434452 its reverse (25443452312), we get a palindrome (46768886764).

The spelling of 21325434452 in words is "twenty-one billion, three hundred twenty-five million, four hundred thirty-four thousand, four hundred fifty-two".