21231201313 has 4 divisors (see below), whose sum is σ = 24264230080. Its totient is φ = 18198172548.

The previous prime is 21231201301. The next prime is 21231201317. The reversal of 21231201313 is 31310213212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21231201313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21231201317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1516514373 + ... + 1516514386.

It is an arithmetic number, because the mean of its divisors is an integer number (6066057520).

Almost surely, 2^21231201313 is an apocalyptic number.

It is an amenable number.

21231201313 is a deficient number, since it is larger than the sum of its proper divisors (3033028767).

21231201313 is an equidigital number, since it uses as much as digits as its factorization.

21231201313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3033028766.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21231201313 its reverse (31310213212), we get a palindrome (52541414525).

The spelling of 21231201313 in words is "twenty-one billion, two hundred thirty-one million, two hundred one thousand, three hundred thirteen".