213121313 has 2 divisors, whose sum is σ = 213121314. Its totient is φ = 213121312.

The previous prime is 213121303. The next prime is 213121343. The reversal of 213121313 is 313121312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 178275904 + 34845409 = 13352^2 + 5903^2 .

It is a cyclic number.

It is not a de Polignac number, because 213121313 - 2⁸ = 213121057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 213121291 and 213121300.

It is not a weakly prime, because it can be changed into another prime (213121303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106560656 + 106560657.

It is an arithmetic number, because the mean of its divisors is an integer number (106560657).

Almost surely, 2^213121313 is an apocalyptic number.

It is an amenable number.

213121313 is a deficient number, since it is larger than the sum of its proper divisors (1).

213121313 is an equidigital number, since it uses as much as digits as its factorization.

213121313 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108, while the sum is 17.

The square root of 213121313 is about 14598.6750426194. The cubic root of 213121313 is about 597.3226195682.

Adding to 213121313 its reverse (313121312), we get a palindrome (526242625).

Subtracting 213121313 from its reverse (313121312), we obtain a palindrome (99999999).

The spelling of 213121313 in words is "two hundred thirteen million, one hundred twenty-one thousand, three hundred thirteen".