19404409 has 2 divisors, whose sum is σ = 19404410. Its totient is φ = 19404408.

The previous prime is 19404397. The next prime is 19404443. The reversal of 19404409 is 90440491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16933225 + 2471184 = 4115^2 + 1572^2 .

It is a cyclic number.

It is not a de Polignac number, because 19404409 - 2¹⁵ = 19371641 is a prime.

It is not a weakly prime, because it can be changed into another prime (19404449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9702204 + 9702205.

It is an arithmetic number, because the mean of its divisors is an integer number (9702205).

Almost surely, 2^19404409 is an apocalyptic number.

It is an amenable number.

19404409 is a deficient number, since it is larger than the sum of its proper divisors (1).

19404409 is an equidigital number, since it uses as much as digits as its factorization.

19404409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 19404409 is about 4405.0435866175. The cubic root of 19404409 is about 268.7200922911.

It can be divided in two parts, 1940440 and 9, that added together give a square (1940449 = 1393²).

The spelling of 19404409 in words is "nineteen million, four hundred four thousand, four hundred nine".