19679711309 has 4 divisors (see below), whose sum is σ = 20837341404. Its totient is φ = 18522081216.

The previous prime is 19679711299. The next prime is 19679711333. The reversal of 19679711309 is 90311797691.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17584086025 + 2095625284 = 132605^2 + 45778^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19679711309 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 (19679711809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 578815022 + ... + 578815055.

It is an arithmetic number, because the mean of its divisors is an integer number (5209335351).

Almost surely, 2^19679711309 is an apocalyptic number.

It is an amenable number.

19679711309 is a deficient number, since it is larger than the sum of its proper divisors (1157630095).

19679711309 is a wasteful number, since it uses less digits than its factorization.

19679711309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1157630094.

The product of its (nonzero) digits is 642978, while the sum is 53.

The spelling of 19679711309 in words is "nineteen billion, six hundred seventy-nine million, seven hundred eleven thousand, three hundred nine".