213338509 has 2 divisors, whose sum is σ = 213338510. Its totient is φ = 213338508.

The previous prime is 213338507. The next prime is 213338549. The reversal of 213338509 is 905833312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 150136009 + 63202500 = 12253^2 + 7950^2 .

It is a cyclic number.

It is not a de Polignac number, because 213338509 - 2¹ = 213338507 is a prime.

Together with 213338507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213338507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106669254 + 106669255.

It is an arithmetic number, because the mean of its divisors is an integer number (106669255).

Almost surely, 2^213338509 is an apocalyptic number.

It is an amenable number.

213338509 is a deficient number, since it is larger than the sum of its proper divisors (1).

213338509 is an equidigital number, since it uses as much as digits as its factorization.

213338509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 213338509 is about 14606.1120425663. The cubic root of 213338509 is about 597.5254649721.

The spelling of 213338509 in words is "two hundred thirteen million, three hundred thirty-eight thousand, five hundred nine".