19989579491 has 8 divisors (see below), whose sum is σ = 22985389824. Its totient is φ = 17028808200.

The previous prime is 19989579469. The next prime is 19989579497. The reversal of 19989579491 is 19497598991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19989579491 - 2¹⁰ = 19989578467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19989579497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8758535 + ... + 8760816.

It is an arithmetic number, because the mean of its divisors is an integer number (2873173728).

Almost surely, 2^19989579491 is an apocalyptic number.

19989579491 is a deficient number, since it is larger than the sum of its proper divisors (2995810333).

19989579491 is a wasteful number, since it uses less digits than its factorization.

19989579491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17519521.

The product of its digits is 66134880, while the sum is 71.

The spelling of 19989579491 in words is "nineteen billion, nine hundred eighty-nine million, five hundred seventy-nine thousand, four hundred ninety-one".