19445309 has 6 divisors (see below), whose sum is σ = 21056346. Its totient is φ = 17949360.

The previous prime is 19445269. The next prime is 19445311. The reversal of 19445309 is 90354491.

It can be written as a sum of positive squares in 3 ways, for example, as 765625 + 18679684 = 875^2 + 4322^2 .

It is not a de Polignac number, because 19445309 - 2²⁴ = 2668093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19445359) 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 in 5 ways as a sum of consecutive naturals, for example, 57362 + ... + 57699.

It is an arithmetic number, because the mean of its divisors is an integer number (3509391).

Almost surely, 2^19445309 is an apocalyptic number.

It is an amenable number.

19445309 is a deficient number, since it is larger than the sum of its proper divisors (1611037).

19445309 is a wasteful number, since it uses less digits than its factorization.

19445309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115087 (or 115074 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 19445309 is about 4409.6835487368. The cubic root of 19445309 is about 268.9087597032.

The spelling of 19445309 in words is "nineteen million, four hundred forty-five thousand, three hundred nine".