21431231344 has 20 divisors (see below), whose sum is σ = 41537374920. Its totient is φ = 10711908800.

The previous prime is 21431231281. The next prime is 21431231357. The reversal of 21431231344 is 44313213412.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183682 + ... + 276769.

It is an arithmetic number, because the mean of its divisors is an integer number (2076868746).

Almost surely, 2^21431231344 is an apocalyptic number.

It is an amenable number.

21431231344 is a deficient number, since it is larger than the sum of its proper divisors (20106143576).

21431231344 is a wasteful number, since it uses less digits than its factorization.

21431231344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463368 (or 463362 counting only the distinct ones).

The product of its digits is 6912, while the sum is 28.

Adding to 21431231344 its reverse (44313213412), we get a palindrome (65744444756).

The spelling of 21431231344 in words is "twenty-one billion, four hundred thirty-one million, two hundred thirty-one thousand, three hundred forty-four".