19941814991 has 4 divisors (see below), whose sum is σ = 22790645712. Its totient is φ = 17092984272.

The previous prime is 19941814987. The next prime is 19941814999.

19941814991 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 19941814991 - 2² = 19941814987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19941814999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1424415350 + ... + 1424415363.

It is an arithmetic number, because the mean of its divisors is an integer number (5697661428).

Almost surely, 2^19941814991 is an apocalyptic number.

19941814991 is a deficient number, since it is larger than the sum of its proper divisors (2848830721).

19941814991 is an equidigital number, since it uses as much as digits as its factorization.

19941814991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2848830720.

The product of its digits is 839808, while the sum is 56.

The spelling of 19941814991 in words is "nineteen billion, nine hundred forty-one million, eight hundred fourteen thousand, nine hundred ninety-one".