404042209 has 2 divisors, whose sum is σ = 404042210. Its totient is φ = 404042208.

The previous prime is 404042203. The next prime is 404042231. The reversal of 404042209 is 902240404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 349577809 + 54464400 = 18697^2 + 7380^2 .

It is a cyclic number.

It is not a de Polignac number, because 404042209 - 2²⁷ = 269824481 is a prime.

It is not a weakly prime, because it can be changed into another prime (404042203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202021104 + 202021105.

It is an arithmetic number, because the mean of its divisors is an integer number (202021105).

Almost surely, 2^404042209 is an apocalyptic number.

It is an amenable number.

404042209 is a deficient number, since it is larger than the sum of its proper divisors (1).

404042209 is an equidigital number, since it uses as much as digits as its factorization.

404042209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 404042209 is about 20100.8012029372. The cubic root of 404042209 is about 739.2799234726.

The spelling of 404042209 in words is "four hundred four million, forty-two thousand, two hundred nine".