21344434431 has 8 divisors (see below), whose sum is σ = 28460269824. Its totient is φ = 14229111000.

The previous prime is 21344434417. The next prime is 21344434469. The reversal of 21344434431 is 13443444312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21344434431 - 2⁵ = 21344434399 is a prime.

It is a super-2 number, since 2×21344434431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21344434392 and 21344434401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21344434411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16945 + ... + 207306.

It is an arithmetic number, because the mean of its divisors is an integer number (3557533728).

Almost surely, 2^21344434431 is an apocalyptic number.

21344434431 is a deficient number, since it is larger than the sum of its proper divisors (7115835393).

21344434431 is a wasteful number, since it uses less digits than its factorization.

21344434431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255981.

The product of its digits is 55296, while the sum is 33.

Adding to 21344434431 its reverse (13443444312), we get a palindrome (34787878743).

The spelling of 21344434431 in words is "twenty-one billion, three hundred forty-four million, four hundred thirty-four thousand, four hundred thirty-one".