28181424 has 40 divisors (see below), whose sum is σ = 73535472. Its totient is φ = 9299200.

The previous prime is 28181399. The next prime is 28181429. The reversal of 28181424 is 42418182.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 28181391 and 28181400.

It is not an unprimeable number, because it can be changed into a prime (28181429) 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 7 ways as a sum of consecutive naturals, for example, 1942 + ... + 7754.

Almost surely, 2^28181424 is an apocalyptic number.

28181424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28181424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36767736).

28181424 is an abundant number, since it is smaller than the sum of its proper divisors (45354048).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28181424 is a wasteful number, since it uses less digits than its factorization.

28181424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5925 (or 5919 counting only the distinct ones).

The product of its digits is 4096, while the sum is 30.

The square root of 28181424 is about 5308.6178992276. The cubic root of 28181424 is about 304.3133311416.

The spelling of 28181424 in words is "twenty-eight million, one hundred eighty-one thousand, four hundred twenty-four".