19859594813 has 4 divisors (see below), whose sum is σ = 20139307488. Its totient is φ = 19579882140.

The previous prime is 19859594771. The next prime is 19859594863. The reversal of 19859594813 is 31849595891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31849595891 = 15299 ⋅2081809.

It is a cyclic number.

It is not a de Polignac number, because 19859594813 - 2⁶ = 19859594749 is a prime.

It is a super-2 number, since 2×19859594813² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19859594863) 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, 139856231 + ... + 139856372.

It is an arithmetic number, because the mean of its divisors is an integer number (5034826872).

Almost surely, 2^19859594813 is an apocalyptic number.

It is an amenable number.

19859594813 is a deficient number, since it is larger than the sum of its proper divisors (279712675).

19859594813 is an equidigital number, since it uses as much as digits as its factorization.

19859594813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279712674.

The product of its digits is 13996800, while the sum is 62.

The spelling of 19859594813 in words is "nineteen billion, eight hundred fifty-nine million, five hundred ninety-four thousand, eight hundred thirteen".