19191161591 has 12 divisors (see below), whose sum is σ = 22927777128. Its totient is φ = 16004982672.

The previous prime is 19191161557. The next prime is 19191161593. The reversal of 19191161591 is 19516119191.

It is a happy number.

It is not a de Polignac number, because 19191161591 - 2¹⁸ = 19190899447 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 (19191161593) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5290841 + ... + 5294466.

It is an arithmetic number, because the mean of its divisors is an integer number (1910648094).

Almost surely, 2^19191161591 is an apocalyptic number.

19191161591 is a deficient number, since it is larger than the sum of its proper divisors (3736615537).

19191161591 is a wasteful number, since it uses less digits than its factorization.

19191161591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10585358 (or 10585351 counting only the distinct ones).

The product of its digits is 21870, while the sum is 44.

The spelling of 19191161591 in words is "nineteen billion, one hundred ninety-one million, one hundred sixty-one thousand, five hundred ninety-one".