28238623 has 4 divisors (see below), whose sum is σ = 32272720. Its totient is φ = 24204528.

The previous prime is 28238621. The next prime is 28238633. The reversal of 28238623 is 32683282.

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 28238623 - 2¹ = 28238621 is a prime.

It is a super-2 number, since 2×28238623² = 1594839657872258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28238621) 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, 2017038 + ... + 2017051.

It is an arithmetic number, because the mean of its divisors is an integer number (8068180).

Almost surely, 2^28238623 is an apocalyptic number.

28238623 is a deficient number, since it is larger than the sum of its proper divisors (4034097).

28238623 is an equidigital number, since it uses as much as digits as its factorization.

28238623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4034096.

The product of its digits is 27648, while the sum is 34.

The square root of 28238623 is about 5314.0025404586. The cubic root of 28238623 is about 304.5190772513.

The spelling of 28238623 in words is "twenty-eight million, two hundred thirty-eight thousand, six hundred twenty-three".