21144432323 has 6 divisors (see below), whose sum is σ = 24596584596. Its totient is φ = 18123799092.

The previous prime is 21144432307. The next prime is 21144432343. The reversal of 21144432323 is 32323444112.

It is not a de Polignac number, because 21144432323 - 2⁴ = 21144432307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21144432343) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 215759465 + ... + 215759562.

It is an arithmetic number, because the mean of its divisors is an integer number (4099430766).

Almost surely, 2^21144432323 is an apocalyptic number.

21144432323 is a deficient number, since it is larger than the sum of its proper divisors (3452152273).

21144432323 is an equidigital number, since it uses as much as digits as its factorization.

21144432323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431519041 (or 431519034 counting only the distinct ones).

The product of its digits is 13824, while the sum is 29.

Adding to 21144432323 its reverse (32323444112), we get a palindrome (53467876435).

The spelling of 21144432323 in words is "twenty-one billion, one hundred forty-four million, four hundred thirty-two thousand, three hundred twenty-three".