21313120313 has 2 divisors, whose sum is σ = 21313120314. Its totient is φ = 21313120312.

The previous prime is 21313120273. The next prime is 21313120319. The reversal of 21313120313 is 31302131312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11430175744 + 9882944569 = 106912^2 + 99413^2 .

It is a cyclic number.

It is not a de Polignac number, because 21313120313 - 2¹² = 21313116217 is a prime.

It is not a weakly prime, because it can be changed into another prime (21313120319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656560156 + 10656560157.

It is an arithmetic number, because the mean of its divisors is an integer number (10656560157).

Almost surely, 2^21313120313 is an apocalyptic number.

It is an amenable number.

21313120313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21313120313 is an equidigital number, since it uses as much as digits as its factorization.

21313120313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 21313120313 its reverse (31302131312), we get a palindrome (52615251625).

The spelling of 21313120313 in words is "twenty-one billion, three hundred thirteen million, one hundred twenty thousand, three hundred thirteen".