1909181910931 has 2 divisors, whose sum is σ = 1909181910932. Its totient is φ = 1909181910930.

The previous prime is 1909181910929. The next prime is 1909181911031. The reversal of 1909181910931 is 1390191819091.

It is a weak prime.

It is an emirp because it is prime and its reverse (1390191819091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1909181910931 - 2¹ = 1909181910929 is a prime.

It is a super-2 number, since 2×1909181910931² (a number of 25 digits) contains 22 as substring.

Together with 1909181910929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1909181910731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954590955465 + 954590955466.

It is an arithmetic number, because the mean of its divisors is an integer number (954590955466).

Almost surely, 2^{1909181910931} is an apocalyptic number.

1909181910931 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909181910931 is an equidigital number, since it uses as much as digits as its factorization.

1909181910931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 52.

The spelling of 1909181910931 in words is "one trillion, nine hundred nine billion, one hundred eighty-one million, nine hundred ten thousand, nine hundred thirty-one".