28840429 has 4 divisors (see below), whose sum is σ = 29024284. Its totient is φ = 28656576.

The previous prime is 28840417. The next prime is 28840463. The reversal of 28840429 is 92404882.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92404882 = 2 ⋅46202441.

It can be written as a sum of positive squares in 2 ways, for example, as 3337929 + 25502500 = 1827^2 + 5050^2 .

It is a cyclic number.

It is not a de Polignac number, because 28840429 - 2⁵ = 28840397 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 (20840429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91692 + ... + 92005.

It is an arithmetic number, because the mean of its divisors is an integer number (7256071).

Almost surely, 2^28840429 is an apocalyptic number.

It is an amenable number.

28840429 is a deficient number, since it is larger than the sum of its proper divisors (183855).

28840429 is a wasteful number, since it uses less digits than its factorization.

28840429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183854.

The product of its (nonzero) digits is 36864, while the sum is 37.

The square root of 28840429 is about 5370.3285746777. The cubic root of 28840429 is about 306.6671370241.

The spelling of 28840429 in words is "twenty-eight million, eight hundred forty thousand, four hundred twenty-nine".