28240123 has 4 divisors (see below), whose sum is σ = 28627048. Its totient is φ = 27853200.

The previous prime is 28240117. The next prime is 28240153. The reversal of 28240123 is 32104282.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28240123 - 2¹⁷ = 28109051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28240094 and 28240103.

It is not an unprimeable number, because it can be changed into a prime (28240153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193353 + ... + 193498.

It is an arithmetic number, because the mean of its divisors is an integer number (7156762).

Almost surely, 2^28240123 is an apocalyptic number.

28240123 is a deficient number, since it is larger than the sum of its proper divisors (386925).

28240123 is an equidigital number, since it uses as much as digits as its factorization.

28240123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386924.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 28240123 is about 5314.1436751371. The cubic root of 28240123 is about 304.5244690455.

The spelling of 28240123 in words is "twenty-eight million, two hundred forty thousand, one hundred twenty-three".