28378269 has 24 divisors (see below), whose sum is σ = 43985760. Its totient is φ = 18261936.

The previous prime is 28378261. The next prime is 28378279. The reversal of 28378269 is 96287382.

It is not a de Polignac number, because 28378269 - 2³ = 28378261 is a prime.

It is a super-2 number, since 2×28378269² = 1610652302872722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28378261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5034 + ... + 9060.

It is an arithmetic number, because the mean of its divisors is an integer number (1832740).

Almost surely, 2^28378269 is an apocalyptic number.

28378269 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28378269 is a deficient number, since it is larger than the sum of its proper divisors (15607491).

28378269 is an equidigital number, since it uses as much as digits as its factorization.

28378269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4071 (or 4059 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 28378269 is about 5327.1257728723. The cubic root of 28378269 is about 305.0202226133.

The spelling of 28378269 in words is "twenty-eight million, three hundred seventy-eight thousand, two hundred sixty-nine".