28123207 has 12 divisors (see below), whose sum is σ = 32811480. Its totient is φ = 24034416.

The previous prime is 28123201. The next prime is 28123213. The reversal of 28123207 is 70232182.

It is an interprime number because it is at equal distance from previous prime (28123201) and next prime (28123213).

It is not a de Polignac number, because 28123207 - 2²³ = 19734599 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 (28123201) 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 11 ways as a sum of consecutive naturals, for example, 22269 + ... + 23497.

It is an arithmetic number, because the mean of its divisors is an integer number (2734290).

Almost surely, 2^28123207 is an apocalyptic number.

28123207 is a deficient number, since it is larger than the sum of its proper divisors (4688273).

28123207 is a wasteful number, since it uses less digits than its factorization.

28123207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1710 (or 1703 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 28123207 is about 5303.1318105437. The cubic root of 28123207 is about 304.1036371891.

Adding to 28123207 its reverse (70232182), we get a palindrome (98355389).

The spelling of 28123207 in words is "twenty-eight million, one hundred twenty-three thousand, two hundred seven".