19726763689 has 2 divisors, whose sum is σ = 19726763690. Its totient is φ = 19726763688.

The previous prime is 19726763653. The next prime is 19726763713. The reversal of 19726763689 is 98636762791.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12688896025 + 7037867664 = 112645^2 + 83892^2 .

It is a cyclic number.

It is not a de Polignac number, because 19726763689 - 2¹⁵ = 19726730921 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19726763689.

It is not a weakly prime, because it can be changed into another prime (19726763629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9863381844 + 9863381845.

It is an arithmetic number, because the mean of its divisors is an integer number (9863381845).

Almost surely, 2^19726763689 is an apocalyptic number.

It is an amenable number.

19726763689 is a deficient number, since it is larger than the sum of its proper divisors (1).

19726763689 is an equidigital number, since it uses as much as digits as its factorization.

19726763689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41150592, while the sum is 64.

The spelling of 19726763689 in words is "nineteen billion, seven hundred twenty-six million, seven hundred sixty-three thousand, six hundred eighty-nine".