213006809 has 2 divisors, whose sum is σ = 213006810. Its totient is φ = 213006808.

The previous prime is 213006803. The next prime is 213006823. The reversal of 213006809 is 908600312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184416400 + 28590409 = 13580^2 + 5347^2 .

It is a cyclic number.

It is not a de Polignac number, because 213006809 - 2⁸ = 213006553 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (213006803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106503404 + 106503405.

It is an arithmetic number, because the mean of its divisors is an integer number (106503405).

Almost surely, 2^213006809 is an apocalyptic number.

It is an amenable number.

213006809 is a deficient number, since it is larger than the sum of its proper divisors (1).

213006809 is an equidigital number, since it uses as much as digits as its factorization.

213006809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 213006809 is about 14594.7527899585. The cubic root of 213006809 is about 597.2156256048.

The spelling of 213006809 in words is "two hundred thirteen million, six thousand, eight hundred nine".