19946664991 has 12 divisors (see below), whose sum is σ = 22039661952. Its totient is φ = 18038372000.

The previous prime is 19946664979. The next prime is 19946665001.

19946664991 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 19946664991 - 2⁷ = 19946664863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19946664901) 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 in 11 ways as a sum of consecutive naturals, for example, 408430 + ... + 454651.

It is an arithmetic number, because the mean of its divisors is an integer number (1836638496).

Almost surely, 2^19946664991 is an apocalyptic number.

19946664991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

19946664991 is a deficient number, since it is larger than the sum of its proper divisors (2092996961).

19946664991 is a wasteful number, since it uses less digits than its factorization.

19946664991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 863294 (or 863283 counting only the distinct ones).

The product of its digits is 22674816, while the sum is 64.

The spelling of 19946664991 in words is "nineteen billion, nine hundred forty-six million, six hundred sixty-four thousand, nine hundred ninety-one".