28689823 has 2 divisors, whose sum is σ = 28689824. Its totient is φ = 28689822.

The previous prime is 28689811. The next prime is 28689833. The reversal of 28689823 is 32898682.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28689823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28689833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14344911 + 14344912.

It is an arithmetic number, because the mean of its divisors is an integer number (14344912).

Almost surely, 2^28689823 is an apocalyptic number.

28689823 is a deficient number, since it is larger than the sum of its proper divisors (1).

28689823 is an equidigital number, since it uses as much as digits as its factorization.

28689823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 331776, while the sum is 46.

The square root of 28689823 is about 5356.2881737263. The cubic root of 28689823 is about 306.1323953269.

It can be divided in two parts, 286 and 89823, that added together give a palindrome (90109).

The spelling of 28689823 in words is "twenty-eight million, six hundred eighty-nine thousand, eight hundred twenty-three".