19740671987 has 2 divisors, whose sum is σ = 19740671988. Its totient is φ = 19740671986.

The previous prime is 19740671969. The next prime is 19740672011. The reversal of 19740671987 is 78917604791.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19740671987 - 2²⁰ = 19739623411 is a prime.

It is not a weakly prime, because it can be changed into another prime (19740671387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9870335993 + 9870335994.

It is an arithmetic number, because the mean of its divisors is an integer number (9870335994).

Almost surely, 2^19740671987 is an apocalyptic number.

19740671987 is a deficient number, since it is larger than the sum of its proper divisors (1).

19740671987 is an equidigital number, since it uses as much as digits as its factorization.

19740671987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5334336, while the sum is 59.

The spelling of 19740671987 in words is "nineteen billion, seven hundred forty million, six hundred seventy-one thousand, nine hundred eighty-seven".