1981049192689 has 8 divisors (see below), whose sum is σ = 2310261449600. Its totient is φ = 1698042164868.

The previous prime is 1981049192579. The next prime is 1981049192711. The reversal of 1981049192689 is 9862919401891.

It is not a de Polignac number, because 1981049192689 - 2¹¹ = 1981049190641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1981049192189) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2887826469 + ... + 2887827154.

It is an arithmetic number, because the mean of its divisors is an integer number (288782681200).

Almost surely, 2^{1981049192689} is an apocalyptic number.

It is an amenable number.

1981049192689 is a deficient number, since it is larger than the sum of its proper divisors (329212256911).

1981049192689 is an frugal number, since it uses more digits than its factorization.

1981049192689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5775653644 (or 5775653630 counting only the distinct ones).

The product of its (nonzero) digits is 20155392, while the sum is 67.

The spelling of 1981049192689 in words is "one trillion, nine hundred eighty-one billion, forty-nine million, one hundred ninety-two thousand, six hundred eighty-nine".