1999872293609 has 2 divisors, whose sum is σ = 1999872293610. Its totient is φ = 1999872293608.

The previous prime is 1999872293591. The next prime is 1999872293621. The reversal of 1999872293609 is 9063922789991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1331162137600 + 668710156009 = 1153760^2 + 817747^2 .

It is a cyclic number.

It is not a de Polignac number, because 1999872293609 - 2⁴⁰ = 900360665833 is a prime.

It is not a weakly prime, because it can be changed into another prime (1999872290609) 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 as a sum of consecutive naturals, namely, 999936146804 + 999936146805.

It is an arithmetic number, because the mean of its divisors is an integer number (999936146805).

Almost surely, 2^{1999872293609} is an apocalyptic number.

It is an amenable number.

1999872293609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999872293609 is an equidigital number, since it uses as much as digits as its factorization.

1999872293609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 238085568, while the sum is 74.

The spelling of 1999872293609 in words is "one trillion, nine hundred ninety-nine billion, eight hundred seventy-two million, two hundred ninety-three thousand, six hundred nine".