28318389 has 16 divisors (see below), whose sum is σ = 41470464. Its totient is φ = 17046000.

The previous prime is 28318387. The next prime is 28318391. The reversal of 28318389 is 98381382.

It is an interprime number because it is at equal distance from previous prime (28318387) and next prime (28318391).

It is not a de Polignac number, because 28318389 - 2¹ = 28318387 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28318389.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28318387) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2142 + ... + 7824.

It is an arithmetic number, because the mean of its divisors is an integer number (2591904).

Almost surely, 2^28318389 is an apocalyptic number.

It is an amenable number.

28318389 is a deficient number, since it is larger than the sum of its proper divisors (13152075).

28318389 is a wasteful number, since it uses less digits than its factorization.

28318389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5848.

The product of its digits is 82944, while the sum is 42.

The square root of 28318389 is about 5321.5025133885. The cubic root of 28318389 is about 304.8055340134.

The spelling of 28318389 in words is "twenty-eight million, three hundred eighteen thousand, three hundred eighty-nine".