999991000019 has 4 divisors (see below), whose sum is σ = 1090899272760. Its totient is φ = 909082727280.

The previous prime is 999991000003. The next prime is 999991000103. The reversal of 999991000019 is 910000199999.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 999991000019 - 2⁴ = 999991000003 is a prime.

It is a super-2 number, since 2×999991000019² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (999991000819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45454136354 + ... + 45454136375.

It is an arithmetic number, because the mean of its divisors is an integer number (272724818190).

Almost surely, 2^999991000019 is an apocalyptic number.

999991000019 is a deficient number, since it is larger than the sum of its proper divisors (90908272741).

999991000019 is a wasteful number, since it uses less digits than its factorization.

999991000019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90908272740.

The product of its (nonzero) digits is 531441, while the sum is 56.

The spelling of 999991000019 in words is "nine hundred ninety-nine billion, nine hundred ninety-one million, nineteen", and thus it is an aban number.