21444774313 has 4 divisors (see below), whose sum is σ = 21445278660. Its totient is φ = 21444269968.

The previous prime is 21444774311. The next prime is 21444774317. The reversal of 21444774313 is 31347744412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6708756649 + 14736017664 = 81907^2 + 121392^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444774313 - 2¹ = 21444774311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21444774311) 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, 181858 + ... + 275611.

It is an arithmetic number, because the mean of its divisors is an integer number (5361319665).

Almost surely, 2^21444774313 is an apocalyptic number.

It is an amenable number.

21444774313 is a deficient number, since it is larger than the sum of its proper divisors (504347).

21444774313 is an equidigital number, since it uses as much as digits as its factorization.

21444774313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504346.

The product of its digits is 225792, while the sum is 40.

The spelling of 21444774313 in words is "twenty-one billion, four hundred forty-four million, seven hundred seventy-four thousand, three hundred thirteen".