1997009009 has 2 divisors, whose sum is σ = 1997009010. Its totient is φ = 1997009008.

The previous prime is 1997008973. The next prime is 1997009059. The reversal of 1997009009 is 9009007991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1095808609 + 901200400 = 33103^2 + 30020^2 .

It is a cyclic number.

It is not a de Polignac number, because 1997009009 - 2²⁴ = 1980231793 is a prime.

It is a Sophie Germain prime.

1997009009 is a modest number, since divided by 9009 gives 1997 as remainder.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1997009059) 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, 998504504 + 998504505.

It is an arithmetic number, because the mean of its divisors is an integer number (998504505).

Almost surely, 2^1997009009 is an apocalyptic number.

It is an amenable number.

1997009009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1997009009 is an equidigital number, since it uses as much as digits as its factorization.

1997009009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 1997009009 is about 44687.9067422049. The cubic root of 1997009009 is about 1259.2926677897.

The spelling of 1997009009 in words is "one billion, nine hundred ninety-seven million, nine thousand, nine".