19409609 has 2 divisors, whose sum is σ = 19409610. Its totient is φ = 19409608.

The previous prime is 19409581. The next prime is 19409617. The reversal of 19409609 is 90690491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16024009 + 3385600 = 4003^2 + 1840^2 .

It is an emirp because it is prime and its reverse (90690491) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19409609 is a prime.

It is not a weakly prime, because it can be changed into another prime (19409639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9704804 + 9704805.

It is an arithmetic number, because the mean of its divisors is an integer number (9704805).

Almost surely, 2^19409609 is an apocalyptic number.

It is an amenable number.

19409609 is a deficient number, since it is larger than the sum of its proper divisors (1).

19409609 is an equidigital number, since it uses as much as digits as its factorization.

19409609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 19409609 is about 4405.6337796054. The cubic root of 19409609 is about 268.7440940472.

The spelling of 19409609 in words is "nineteen million, four hundred nine thousand, six hundred nine".