19011720091 has 16 divisors (see below), whose sum is σ = 23428488384. Its totient is φ = 15023309184.

The previous prime is 19011720071. The next prime is 19011720097. The reversal of 19011720091 is 19002711091.

It is a happy number.

It is not a de Polignac number, because 19011720091 - 2¹⁷ = 19011589019 is a prime.

It is a super-2 number, since 2×19011720091² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19011720097) 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, 58540 + ... + 203593.

It is an arithmetic number, because the mean of its divisors is an integer number (1464280524).

Almost surely, 2^19011720091 is an apocalyptic number.

19011720091 is a deficient number, since it is larger than the sum of its proper divisors (4416768293).

19011720091 is a wasteful number, since it uses less digits than its factorization.

19011720091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262950.

The product of its (nonzero) digits is 1134, while the sum is 31.

The spelling of 19011720091 in words is "nineteen billion, eleven million, seven hundred twenty thousand, ninety-one".