19660006691 has 8 divisors (see below), whose sum is σ = 21175166544. Its totient is φ = 18145254240.

The previous prime is 19660006679. The next prime is 19660006739.

19660006691 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19660006691 - 2¹⁸ = 19659744547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19660008691) 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, 2336 + ... + 198306.

It is an arithmetic number, because the mean of its divisors is an integer number (2646895818).

Almost surely, 2^19660006691 is an apocalyptic number.

19660006691 is a deficient number, since it is larger than the sum of its proper divisors (1515159853).

19660006691 is a wasteful number, since it uses less digits than its factorization.

19660006691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203701.

The product of its (nonzero) digits is 104976, while the sum is 44.

The spelling of 19660006691 in words is "nineteen billion, six hundred sixty million, six thousand, six hundred ninety-one".