21312320313 has 16 divisors (see below), whose sum is σ = 29544048000. Its totient is φ = 13649328000.

The previous prime is 21312320251. The next prime is 21312320327. The reversal of 21312320313 is 31302321312.

It is not a de Polignac number, because 21312320313 - 2⁹ = 21312319801 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21312320313.

It is not an unprimeable number, because it can be changed into a prime (21312320363) 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 15 ways as a sum of consecutive naturals, for example, 598188 + ... + 632813.

It is an arithmetic number, because the mean of its divisors is an integer number (1846503000).

Almost surely, 2^21312320313 is an apocalyptic number.

It is an amenable number.

21312320313 is a deficient number, since it is larger than the sum of its proper divisors (8231727687).

21312320313 is a wasteful number, since it uses less digits than its factorization.

21312320313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1231232.

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 21312320313 its reverse (31302321312), we get a palindrome (52614641625).

Subtracting 21312320313 from its reverse (31302321312), we obtain a palindrome (9990000999).

The spelling of 21312320313 in words is "twenty-one billion, three hundred twelve million, three hundred twenty thousand, three hundred thirteen".