1990804999 has 2 divisors, whose sum is σ = 1990805000. Its totient is φ = 1990804998.

The previous prime is 1990804987. The next prime is 1990805039. The reversal of 1990804999 is 9994080991.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990804999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1990804919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995402499 + 995402500.

It is an arithmetic number, because the mean of its divisors is an integer number (995402500).

Almost surely, 2^1990804999 is an apocalyptic number.

1990804999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990804999 is an equidigital number, since it uses as much as digits as its factorization.

1990804999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1889568, while the sum is 58.

The square root of 1990804999 is about 44618.4378816650. The cubic root of 1990804999 is about 1257.9872540988.

The spelling of 1990804999 in words is "one billion, nine hundred ninety million, eight hundred four thousand, nine hundred ninety-nine".