21444285791 has 4 divisors (see below), whose sum is σ = 21500867400. Its totient is φ = 21387704184.

The previous prime is 21444285749. The next prime is 21444285853. The reversal of 21444285791 is 19758244412.

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

It is a cyclic number.

It is not a de Polignac number, because 21444285791 - 2¹⁰ = 21444284767 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 (21444285691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28290236 + ... + 28290993.

It is an arithmetic number, because the mean of its divisors is an integer number (5375216850).

Almost surely, 2^21444285791 is an apocalyptic number.

21444285791 is a deficient number, since it is larger than the sum of its proper divisors (56581609).

21444285791 is an equidigital number, since it uses as much as digits as its factorization.

21444285791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56581608.

The product of its digits is 645120, while the sum is 47.

The spelling of 21444285791 in words is "twenty-one billion, four hundred forty-four million, two hundred eighty-five thousand, seven hundred ninety-one".