28238255 has 4 divisors (see below), whose sum is σ = 33885912. Its totient is φ = 22590600.

The previous prime is 28238251. The next prime is 28238261. The reversal of 28238255 is 55283282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55283282 = 2 ⋅27641641.

It is not a de Polignac number, because 28238255 - 2² = 28238251 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28238251) 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, 2823821 + ... + 2823830.

It is an arithmetic number, because the mean of its divisors is an integer number (8471478).

Almost surely, 2^28238255 is an apocalyptic number.

28238255 is a deficient number, since it is larger than the sum of its proper divisors (5647657).

28238255 is an equidigital number, since it uses as much as digits as its factorization.

28238255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5647656.

The product of its digits is 38400, while the sum is 35.

The square root of 28238255 is about 5313.9679148448. The cubic root of 28238255 is about 304.5177544353.

The spelling of 28238255 in words is "twenty-eight million, two hundred thirty-eight thousand, two hundred fifty-five".