187920378787 has 2 divisors, whose sum is σ = 187920378788. Its totient is φ = 187920378786.

The previous prime is 187920378721. The next prime is 187920378887. The reversal of 187920378787 is 787873029781.

It is a weak prime.

It is an emirp because it is prime and its reverse (787873029781) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187920378787 is a prime.

It is not a weakly prime, because it can be changed into another prime (187920378707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93960189393 + 93960189394.

It is an arithmetic number, because the mean of its divisors is an integer number (93960189394).

Almost surely, 2^187920378787 is an apocalyptic number.

187920378787 is a deficient number, since it is larger than the sum of its proper divisors (1).

187920378787 is an equidigital number, since it uses as much as digits as its factorization.

187920378787 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 66382848, while the sum is 67.

The spelling of 187920378787 in words is "one hundred eighty-seven billion, nine hundred twenty million, three hundred seventy-eight thousand, seven hundred eighty-seven".