213123511 has 2 divisors, whose sum is σ = 213123512. Its totient is φ = 213123510.

The previous prime is 213123487. The next prime is 213123539. The reversal of 213123511 is 115321312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 213123511 - 2¹¹ = 213121463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213123571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106561755 + 106561756.

It is an arithmetic number, because the mean of its divisors is an integer number (106561756).

Almost surely, 2^213123511 is an apocalyptic number.

213123511 is a deficient number, since it is larger than the sum of its proper divisors (1).

213123511 is an equidigital number, since it uses as much as digits as its factorization.

213123511 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 180, while the sum is 19.

The square root of 213123511 is about 14598.7503232297. The cubic root of 213123511 is about 597.3246730319.

Adding to 213123511 its reverse (115321312), we get a palindrome (328444823).

The spelling of 213123511 in words is "two hundred thirteen million, one hundred twenty-three thousand, five hundred eleven".