900409 has 2 divisors, whose sum is σ = 900410. Its totient is φ = 900408.

The previous prime is 900397. The next prime is 900443. The reversal of 900409 is 904009.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 896809 + 3600 = 947^2 + 60^2 .

It is a cyclic number.

It is not a de Polignac number, because 900409 - 2¹¹ = 898361 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 900409.

It is not a weakly prime, because it can be changed into another prime (909409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 450204 + 450205.

It is an arithmetic number, because the mean of its divisors is an integer number (450205).

2⁹⁰⁰⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

900409 is a deficient number, since it is larger than the sum of its proper divisors (1).

900409 is an equidigital number, since it uses as much as digits as its factorization.

900409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 900409 is about 948.8988354930. The cubic root of 900409 is about 96.5635616219.

Subtracting 900409 from its reverse (904009), we obtain a square (3600 = 60²).

The spelling of 900409 in words is "nine hundred thousand, four hundred nine".