28388475 has 36 divisors (see below), whose sum is σ = 52741416. Its totient is φ = 15137280.

The previous prime is 28388473. The next prime is 28388513. The reversal of 28388475 is 57488382.

It is not a de Polignac number, because 28388475 - 2¹ = 28388473 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 28388475.

It is not an unprimeable number, because it can be changed into a prime (28388473) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3739 + ... + 8411.

Almost surely, 2^28388475 is an apocalyptic number.

28388475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28388475 is a deficient number, since it is larger than the sum of its proper divisors (24352941).

28388475 is an equidigital number, since it uses as much as digits as its factorization.

28388475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4698 (or 4681 counting only the distinct ones).

The product of its digits is 430080, while the sum is 45.

The square root of 28388475 is about 5328.0836142088. The cubic root of 28388475 is about 305.0567841958.

The spelling of 28388475 in words is "twenty-eight million, three hundred eighty-eight thousand, four hundred seventy-five".