21312244221313 has 4 divisors (see below), whose sum is σ = 21551707639620. Its totient is φ = 21072780803008.

The previous prime is 21312244221283. The next prime is 21312244221353. The reversal of 21312244221313 is 31312244221312.

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 12456043193344 + 8856201027969 = 3529312^2 + 2975937^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312244221313 - 2¹³ = 21312244213121 is a prime.

It is a super-3 number, since 3×21312244221313³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21312244221353) 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, 119731709020 + ... + 119731709197.

It is an arithmetic number, because the mean of its divisors is an integer number (5387926909905).

Almost surely, 2^{21312244221313} is an apocalyptic number.

It is an amenable number.

21312244221313 is a deficient number, since it is larger than the sum of its proper divisors (239463418307).

21312244221313 is an equidigital number, since it uses as much as digits as its factorization.

21312244221313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239463418306.

The product of its digits is 13824, while the sum is 31.

Adding to 21312244221313 its reverse (31312244221312), we get a palindrome (52624488442625).

Subtracting 21312244221313 from its reverse (31312244221312), we obtain a palindrome (9999999999999).

The spelling of 21312244221313 in words is "twenty-one trillion, three hundred twelve billion, two hundred forty-four million, two hundred twenty-one thousand, three hundred thirteen".