19787269877 has 2 divisors, whose sum is σ = 19787269878. Its totient is φ = 19787269876.

The previous prime is 19787269847. The next prime is 19787269889. The reversal of 19787269877 is 77896278791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12338544241 + 7448725636 = 111079^2 + 86306^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19787269877 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19787269877.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19787269847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9893634938 + 9893634939.

It is an arithmetic number, because the mean of its divisors is an integer number (9893634939).

Almost surely, 2^19787269877 is an apocalyptic number.

It is an amenable number.

19787269877 is a deficient number, since it is larger than the sum of its proper divisors (1).

19787269877 is an equidigital number, since it uses as much as digits as its factorization.

19787269877 is an evil number, because the sum of its binary digits is even.

The product of its digits is 149361408, while the sum is 71.

The spelling of 19787269877 in words is "nineteen billion, seven hundred eighty-seven million, two hundred sixty-nine thousand, eight hundred seventy-seven".