19694249691 has 4 divisors (see below), whose sum is σ = 26258999592. Its totient is φ = 13129499792.

The previous prime is 19694249689. The next prime is 19694249699.

19694249691 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 19694249691 - 2¹ = 19694249689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19694249699) 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, 3282374946 + ... + 3282374951.

It is an arithmetic number, because the mean of its divisors is an integer number (6564749898).

Almost surely, 2^19694249691 is an apocalyptic number.

19694249691 is a deficient number, since it is larger than the sum of its proper divisors (6564749901).

19694249691 is an equidigital number, since it uses as much as digits as its factorization.

19694249691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6564749900.

The product of its digits is 7558272, while the sum is 60.

The spelling of 19694249691 in words is "nineteen billion, six hundred ninety-four million, two hundred forty-nine thousand, six hundred ninety-one".