1011009991909 has 2 divisors, whose sum is σ = 1011009991910. Its totient is φ = 1011009991908.

The previous prime is 1011009991907. The next prime is 1011009991913. The reversal of 1011009991909 is 9091999001101.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 979971304225 + 31038687684 = 989935^2 + 176178^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011009991909 - 2¹ = 1011009991907 is a prime.

Together with 1011009991907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011009991907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505504995954 + 505504995955.

It is an arithmetic number, because the mean of its divisors is an integer number (505504995955).

Almost surely, 2^{1011009991909} is an apocalyptic number.

It is an amenable number.

1011009991909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011009991909 is an equidigital number, since it uses as much as digits as its factorization.

1011009991909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 59049, while the sum is 49.

The spelling of 1011009991909 in words is "one trillion, eleven billion, nine million, nine hundred ninety-one thousand, nine hundred nine".