18428887 has 2 divisors, whose sum is σ = 18428888. Its totient is φ = 18428886.

The previous prime is 18428873. The next prime is 18428909. The reversal of 18428887 is 78882481.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (78882481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18428887 - 2¹⁹ = 17904599 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18428807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9214443 + 9214444.

It is an arithmetic number, because the mean of its divisors is an integer number (9214444).

Almost surely, 2^18428887 is an apocalyptic number.

18428887 is the 2479-th hex number.

18428887 is a deficient number, since it is larger than the sum of its proper divisors (1).

18428887 is an equidigital number, since it uses as much as digits as its factorization.

18428887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 229376, while the sum is 46.

The square root of 18428887 is about 4292.8879556774. The cubic root of 18428887 is about 264.1393079812.

The spelling of 18428887 in words is "eighteen million, four hundred twenty-eight thousand, eight hundred eighty-seven".