19121681919 has 16 divisors (see below), whose sum is σ = 26358773760. Its totient is φ = 12317462880.

The previous prime is 19121681899. The next prime is 19121681921. The reversal of 19121681919 is 91918612191.

It is not a de Polignac number, because 19121681919 - 2²⁴ = 19104904703 is a prime.

It is a super-2 number, since 2×19121681919² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19121681119) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 98724 + ... + 219065.

It is an arithmetic number, because the mean of its divisors is an integer number (1647423360).

Almost surely, 2^19121681919 is an apocalyptic number.

19121681919 is a deficient number, since it is larger than the sum of its proper divisors (7237091841).

19121681919 is a wasteful number, since it uses less digits than its factorization.

19121681919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318470.

The product of its digits is 69984, while the sum is 48.

The spelling of 19121681919 in words is "nineteen billion, one hundred twenty-one million, six hundred eighty-one thousand, nine hundred nineteen".