1999904443 has 2 divisors, whose sum is σ = 1999904444. Its totient is φ = 1999904442.

The previous prime is 1999904419. The next prime is 1999904447. The reversal of 1999904443 is 3444099991.

It is a strong prime.

It is an emirp because it is prime and its reverse (3444099991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1999904443 - 2⁵ = 1999904411 is a prime.

It is a super-2 number, since 2×1999904443² = 7999235562262280498, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1999904447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999952221 + 999952222.

It is an arithmetic number, because the mean of its divisors is an integer number (999952222).

Almost surely, 2^1999904443 is an apocalyptic number.

1999904443 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999904443 is an equidigital number, since it uses as much as digits as its factorization.

1999904443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1259712, while the sum is 52.

The square root of 1999904443 is about 44720.2911774957. The cubic root of 1999904443 is about 1259.9009838627.

The spelling of 1999904443 in words is "one billion, nine hundred ninety-nine million, nine hundred four thousand, four hundred forty-three".