19661377607 has 2 divisors, whose sum is σ = 19661377608. Its totient is φ = 19661377606.

The previous prime is 19661377531. The next prime is 19661377609. The reversal of 19661377607 is 70677316691.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19661377607 - 2¹⁰ = 19661376583 is a prime.

Together with 19661377609, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19661377609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9830688803 + 9830688804.

It is an arithmetic number, because the mean of its divisors is an integer number (9830688804).

Almost surely, 2^19661377607 is an apocalyptic number.

19661377607 is a deficient number, since it is larger than the sum of its proper divisors (1).

19661377607 is an equidigital number, since it uses as much as digits as its factorization.

19661377607 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000376, while the sum is 53.

The spelling of 19661377607 in words is "nineteen billion, six hundred sixty-one million, three hundred seventy-seven thousand, six hundred seven".