19804649107 has 4 divisors (see below), whose sum is σ = 20846999080. Its totient is φ = 18762299136.

The previous prime is 19804649101. The next prime is 19804649129. The reversal of 19804649107 is 70194640891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70194640891 = 17 ⋅4129096523.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19804649107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19804649101) 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 3 ways as a sum of consecutive naturals, for example, 521174958 + ... + 521174995.

It is an arithmetic number, because the mean of its divisors is an integer number (5211749770).

Almost surely, 2^19804649107 is an apocalyptic number.

19804649107 is a deficient number, since it is larger than the sum of its proper divisors (1042349973).

19804649107 is a wasteful number, since it uses less digits than its factorization.

19804649107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1042349972.

The product of its (nonzero) digits is 435456, while the sum is 49.

The spelling of 19804649107 in words is "nineteen billion, eight hundred four million, six hundred forty-nine thousand, one hundred seven".