1999773949 has 2 divisors, whose sum is σ = 1999773950. Its totient is φ = 1999773948.

The previous prime is 1999773917. The next prime is 1999774003. The reversal of 1999773949 is 9493779991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1904711449 + 95062500 = 43643^2 + 9750^2 .

It is a cyclic number.

It is not a de Polignac number, because 1999773949 - 2⁵ = 1999773917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1999773449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999886974 + 999886975.

It is an arithmetic number, because the mean of its divisors is an integer number (999886975).

Almost surely, 2^1999773949 is an apocalyptic number.

It is an amenable number.

1999773949 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999773949 is an equidigital number, since it uses as much as digits as its factorization.

1999773949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34720812, while the sum is 67.

The square root of 1999773949 is about 44718.8321515667. The cubic root of 1999773949 is about 1259.8735803709.

The spelling of 1999773949 in words is "one billion, nine hundred ninety-nine million, seven hundred seventy-three thousand, nine hundred forty-nine".