19980187 has 2 divisors, whose sum is σ = 19980188. Its totient is φ = 19980186.

The previous prime is 19980179. The next prime is 19980211. The reversal of 19980187 is 78108991.

It is a weak prime.

It is an emirp because it is prime and its reverse (78108991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19980187 - 2³ = 19980179 is a prime.

It is not a weakly prime, because it can be changed into another prime (19980167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9990093 + 9990094.

It is an arithmetic number, because the mean of its divisors is an integer number (9990094).

Almost surely, 2^19980187 is an apocalyptic number.

19980187 is a deficient number, since it is larger than the sum of its proper divisors (1).

19980187 is an equidigital number, since it uses as much as digits as its factorization.

19980187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 19980187 is about 4469.9202453735. The cubic root of 19980187 is about 271.3520974506.

The spelling of 19980187 in words is "nineteen million, nine hundred eighty thousand, one hundred eighty-seven".