19695423977 has 2 divisors, whose sum is σ = 19695423978. Its totient is φ = 19695423976.

The previous prime is 19695423929. The next prime is 19695424043. The reversal of 19695423977 is 77932459691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17903510416 + 1791913561 = 133804^2 + 42331^2 .

It is a cyclic number.

It is not a de Polignac number, because 19695423977 - 2¹⁸ = 19695161833 is a prime.

It is not a weakly prime, because it can be changed into another prime (19695423277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9847711988 + 9847711989.

It is an arithmetic number, because the mean of its divisors is an integer number (9847711989).

Almost surely, 2^19695423977 is an apocalyptic number.

It is an amenable number.

19695423977 is a deficient number, since it is larger than the sum of its proper divisors (1).

19695423977 is an equidigital number, since it uses as much as digits as its factorization.

19695423977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25719120, while the sum is 62.

The spelling of 19695423977 in words is "nineteen billion, six hundred ninety-five million, four hundred twenty-three thousand, nine hundred seventy-seven".