402606209 has 2 divisors, whose sum is σ = 402606210. Its totient is φ = 402606208.

The previous prime is 402606203. The next prime is 402606227. The reversal of 402606209 is 902606204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 369715984 + 32890225 = 19228^2 + 5735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-402606209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (402606203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201303104 + 201303105.

It is an arithmetic number, because the mean of its divisors is an integer number (201303105).

Almost surely, 2^402606209 is an apocalyptic number.

It is an amenable number.

402606209 is a deficient number, since it is larger than the sum of its proper divisors (1).

402606209 is an equidigital number, since it uses as much as digits as its factorization.

402606209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 402606209 is about 20065.0494392613. The cubic root of 402606209 is about 738.4030628257.

The spelling of 402606209 in words is "four hundred two million, six hundred six thousand, two hundred nine".