19661377019 has 2 divisors, whose sum is σ = 19661377020. Its totient is φ = 19661377018.

The previous prime is 19661377003. The next prime is 19661377069. The reversal of 19661377019 is 91077316691.

It is an a-pointer prime, because the next prime (19661377069) can be obtained adding 19661377019 to its sum of digits (50).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19661377019 - 2⁴ = 19661377003 is a prime.

It is a super-2 number, since 2×19661377019² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (19661377069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9830688509 + 9830688510.

It is an arithmetic number, because the mean of its divisors is an integer number (9830688510).

Almost surely, 2^19661377019 is an apocalyptic number.

19661377019 is a deficient number, since it is larger than the sum of its proper divisors (1).

19661377019 is an equidigital number, since it uses as much as digits as its factorization.

19661377019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 428652, while the sum is 50.

The spelling of 19661377019 in words is "nineteen billion, six hundred sixty-one million, three hundred seventy-seven thousand, nineteen".