213366509 has 2 divisors, whose sum is σ = 213366510. Its totient is φ = 213366508.

The previous prime is 213366451. The next prime is 213366539. The reversal of 213366509 is 905663312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144841225 + 68525284 = 12035^2 + 8278^2 .

It is a cyclic number.

It is not a de Polignac number, because 213366509 - 2²⁴ = 196589293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213366539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106683254 + 106683255.

It is an arithmetic number, because the mean of its divisors is an integer number (106683255).

Almost surely, 2^213366509 is an apocalyptic number.

It is an amenable number.

213366509 is a deficient number, since it is larger than the sum of its proper divisors (1).

213366509 is an equidigital number, since it uses as much as digits as its factorization.

213366509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 29160, while the sum is 35.

The square root of 213366509 is about 14607.0705139669. The cubic root of 213366509 is about 597.5516049334.

The spelling of 213366509 in words is "two hundred thirteen million, three hundred sixty-six thousand, five hundred nine".