28397223 has 24 divisors (see below), whose sum is σ = 42898128. Its totient is φ = 18771264.

The previous prime is 28397207. The next prime is 28397227. The reversal of 28397223 is 32279382.

It is not a de Polignac number, because 28397223 - 2⁴ = 28397207 is a prime.

It is a super-2 number, since 2×28397223² = 1612804548223458, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28397227) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32865 + ... + 33717.

It is an arithmetic number, because the mean of its divisors is an integer number (1787422).

Almost surely, 2^28397223 is an apocalyptic number.

28397223 is a deficient number, since it is larger than the sum of its proper divisors (14500905).

28397223 is an equidigital number, since it uses as much as digits as its factorization.

28397223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1005 (or 993 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 28397223 is about 5328.9044840380. The cubic root of 28397223 is about 305.0881157212.

It can be divided in two parts, 283972 and 23, that multiplied together give a palindrome (6531356).

The spelling of 28397223 in words is "twenty-eight million, three hundred ninety-seven thousand, two hundred twenty-three".