21231134430 has 64 divisors (see below), whose sum is σ = 55650405888. Its totient is φ = 5141068160.

The previous prime is 21231134429. The next prime is 21231134447. The reversal of 21231134430 is 3443113212.

It is a happy number.

It is a super-2 number, since 2×21231134430² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21231134430.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 256444 + ... + 328976.

It is an arithmetic number, because the mean of its divisors is an integer number (869537592).

Almost surely, 2^21231134430 is an apocalyptic number.

21231134430 is an abundant number, since it is smaller than the sum of its proper divisors (34419271458).

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

21231134430 is a wasteful number, since it uses less digits than its factorization.

21231134430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73441.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21231134430 its reverse (3443113212), we get a palindrome (24674247642).

The spelling of 21231134430 in words is "twenty-one billion, two hundred thirty-one million, one hundred thirty-four thousand, four hundred thirty".