28198459 has 4 divisors (see below), whose sum is σ = 28462104. Its totient is φ = 27934816.

The previous prime is 28198453. The next prime is 28198487. The reversal of 28198459 is 95489182.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95489182 = 2 ⋅47744591.

It is a cyclic number.

It is not a de Polignac number, because 28198459 - 2¹⁵ = 28165691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28198453) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131662 + ... + 131875.

It is an arithmetic number, because the mean of its divisors is an integer number (7115526).

Almost surely, 2^28198459 is an apocalyptic number.

28198459 is a deficient number, since it is larger than the sum of its proper divisors (263645).

28198459 is a wasteful number, since it uses less digits than its factorization.

28198459 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263644.

The product of its digits is 207360, while the sum is 46.

The square root of 28198459 is about 5310.2221234144. Note that the first 3 decimals coincide. The cubic root of 28198459 is about 304.3746355126.

The spelling of 28198459 in words is "twenty-eight million, one hundred ninety-eight thousand, four hundred fifty-nine".