19617814409 has 4 divisors (see below), whose sum is σ = 19838239380. Its totient is φ = 19397389440.

The previous prime is 19617814399. The next prime is 19617814427. The reversal of 19617814409 is 90441871691.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4231892809 + 15385921600 = 65053^2 + 124040^2 .

It is a cyclic number.

It is not a de Polignac number, because 19617814409 - 2²⁴ = 19601037193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19617814499) 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 3 ways as a sum of consecutive naturals, for example, 110212352 + ... + 110212529.

It is an arithmetic number, because the mean of its divisors is an integer number (4959559845).

Almost surely, 2^19617814409 is an apocalyptic number.

It is an amenable number.

19617814409 is a deficient number, since it is larger than the sum of its proper divisors (220424971).

19617814409 is an equidigital number, since it uses as much as digits as its factorization.

19617814409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220424970.

The product of its (nonzero) digits is 435456, while the sum is 50.

The spelling of 19617814409 in words is "nineteen billion, six hundred seventeen million, eight hundred fourteen thousand, four hundred nine".