21144423311 has 4 divisors (see below), whose sum is σ = 23066643624. Its totient is φ = 19222203000.

The previous prime is 21144423283. The next prime is 21144423329. The reversal of 21144423311 is 11332444112.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21144423311 - 2¹⁰ = 21144422287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144423371) 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 3 ways as a sum of consecutive naturals, for example, 961110140 + ... + 961110161.

It is an arithmetic number, because the mean of its divisors is an integer number (5766660906).

Almost surely, 2^21144423311 is an apocalyptic number.

21144423311 is a deficient number, since it is larger than the sum of its proper divisors (1922220313).

21144423311 is a wasteful number, since it uses less digits than its factorization.

21144423311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1922220312.

The product of its digits is 2304, while the sum is 26.

Adding to 21144423311 its reverse (11332444112), we get a palindrome (32476867423).

The spelling of 21144423311 in words is "twenty-one billion, one hundred forty-four million, four hundred twenty-three thousand, three hundred eleven".