21231435452 has 12 divisors (see below), whose sum is σ = 37218312600. Its totient is φ = 10597631856.

The previous prime is 21231435451. The next prime is 21231435469. The reversal of 21231435452 is 25453413212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231435451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4518827 + ... + 4523522.

It is an arithmetic number, because the mean of its divisors is an integer number (3101526050).

Almost surely, 2^21231435452 is an apocalyptic number.

It is an amenable number.

21231435452 is a deficient number, since it is larger than the sum of its proper divisors (15986877148).

21231435452 is a wasteful number, since it uses less digits than its factorization.

21231435452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9042940 (or 9042938 counting only the distinct ones).

The product of its digits is 28800, while the sum is 32.

Adding to 21231435452 its reverse (25453413212), we get a palindrome (46684848664).

The spelling of 21231435452 in words is "twenty-one billion, two hundred thirty-one million, four hundred thirty-five thousand, four hundred fifty-two".