19228987 has 2 divisors, whose sum is σ = 19228988. Its totient is φ = 19228986.

The previous prime is 19228981. The next prime is 19229009. The reversal of 19228987 is 78982291.

It is a weak prime.

It is an emirp because it is prime and its reverse (78982291) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19228987 is a prime.

It is not a weakly prime, because it can be changed into another prime (19228981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9614493 + 9614494.

It is an arithmetic number, because the mean of its divisors is an integer number (9614494).

Almost surely, 2^19228987 is an apocalyptic number.

19228987 is a deficient number, since it is larger than the sum of its proper divisors (1).

19228987 is an equidigital number, since it uses as much as digits as its factorization.

19228987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 46.

The square root of 19228987 is about 4385.0868862544. The cubic root of 19228987 is about 267.9078681973.

The spelling of 19228987 in words is "nineteen million, two hundred twenty-eight thousand, nine hundred eighty-seven".