19713677761 has 4 divisors (see below), whose sum is σ = 19894537300. Its totient is φ = 19532818224.

The previous prime is 19713677749. The next prime is 19713677771. The reversal of 19713677761 is 16777631791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16777631791 = 223 ⋅75236017.

It can be written as a sum of positive squares in 2 ways, for example, as 10151771536 + 9561906225 = 100756^2 + 97785^2 .

It is a cyclic number.

It is not a de Polignac number, because 19713677761 - 2¹⁷ = 19713546689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19713677701) 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, 90429606 + ... + 90429823.

It is an arithmetic number, because the mean of its divisors is an integer number (4973634325).

Almost surely, 2^19713677761 is an apocalyptic number.

It is an amenable number.

19713677761 is a deficient number, since it is larger than the sum of its proper divisors (180859539).

19713677761 is a wasteful number, since it uses less digits than its factorization.

19713677761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180859538.

The product of its digits is 2333772, while the sum is 55.

The spelling of 19713677761 in words is "nineteen billion, seven hundred thirteen million, six hundred seventy-seven thousand, seven hundred sixty-one".