19719682081 has 4 divisors (see below), whose sum is σ = 21512380464. Its totient is φ = 17926983700.

The previous prime is 19719682043. The next prime is 19719682111. The reversal of 19719682081 is 18028691791.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19719682081 is a prime.

It is a super-2 number, since 2×19719682081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19719682001) 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, 896349175 + ... + 896349196.

It is an arithmetic number, because the mean of its divisors is an integer number (5378095116).

Almost surely, 2^19719682081 is an apocalyptic number.

19719682081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

19719682081 is a deficient number, since it is larger than the sum of its proper divisors (1792698383).

19719682081 is a wasteful number, since it uses less digits than its factorization.

19719682081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1792698382.

The product of its (nonzero) digits is 435456, while the sum is 52.

The spelling of 19719682081 in words is "nineteen billion, seven hundred nineteen million, six hundred eighty-two thousand, eighty-one".