19581369409 has 4 divisors (see below), whose sum is σ = 22378707904. Its totient is φ = 16784030916.

The previous prime is 19581369377. The next prime is 19581369413. The reversal of 19581369409 is 90496318591.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19581369409 - 2⁵ = 19581369377 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19581369409.

It is not an unprimeable number, because it can be changed into a prime (19581369439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1398669237 + ... + 1398669250.

It is an arithmetic number, because the mean of its divisors is an integer number (5594676976).

Almost surely, 2^19581369409 is an apocalyptic number.

It is an amenable number.

19581369409 is a deficient number, since it is larger than the sum of its proper divisors (2797338495).

19581369409 is an equidigital number, since it uses as much as digits as its factorization.

19581369409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2797338494.

The product of its (nonzero) digits is 2099520, while the sum is 55.

The spelling of 19581369409 in words is "nineteen billion, five hundred eighty-one million, three hundred sixty-nine thousand, four hundred nine".