19691874845 has 8 divisors (see below), whose sum is σ = 23631227064. Its totient is φ = 15752848384.

The previous prime is 19691874767. The next prime is 19691874857. The reversal of 19691874845 is 54847819691.

It can be written as a sum of positive squares in 4 ways, for example, as 1329185764 + 18362689081 = 36458^2 + 135509^2 .

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 19691874845 - 2²⁶ = 19624765981 is a prime.

It is a super-2 number, since 2×19691874845² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 81017 + ... + 214353.

It is an arithmetic number, because the mean of its divisors is an integer number (2953903383).

Almost surely, 2^19691874845 is an apocalyptic number.

It is an amenable number.

19691874845 is a deficient number, since it is larger than the sum of its proper divisors (3939352219).

19691874845 is a wasteful number, since it uses less digits than its factorization.

19691874845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162879.

The product of its digits is 17418240, while the sum is 62.

The spelling of 19691874845 in words is "nineteen billion, six hundred ninety-one million, eight hundred seventy-four thousand, eight hundred forty-five".