18428873 has 2 divisors, whose sum is σ = 18428874. Its totient is φ = 18428872.

The previous prime is 18428869. The next prime is 18428887. The reversal of 18428873 is 37882481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17330569 + 1098304 = 4163^2 + 1048^2 .

It is a cyclic number.

It is not a de Polignac number, because 18428873 - 2² = 18428869 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18428873.

It is not a weakly prime, because it can be changed into another prime (18428173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9214436 + 9214437.

It is an arithmetic number, because the mean of its divisors is an integer number (9214437).

Almost surely, 2^18428873 is an apocalyptic number.

It is an amenable number.

18428873 is a deficient number, since it is larger than the sum of its proper divisors (1).

18428873 is an equidigital number, since it uses as much as digits as its factorization.

18428873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86016, while the sum is 41.

The square root of 18428873 is about 4292.8863250731. The cubic root of 18428873 is about 264.1392410944.

The spelling of 18428873 in words is "eighteen million, four hundred twenty-eight thousand, eight hundred seventy-three".