28840890 has 32 divisors (see below), whose sum is σ = 74543616. Its totient is φ = 7099200.

The previous prime is 28840883. The next prime is 28840897. The reversal of 28840890 is 9804882.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28840883) and next prime (28840897).

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28840897) 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 15 ways as a sum of consecutive naturals, for example, 36586 + ... + 37365.

It is an arithmetic number, because the mean of its divisors is an integer number (2329488).

Almost surely, 2^28840890 is an apocalyptic number.

28840890 is an abundant number, since it is smaller than the sum of its proper divisors (45702726).

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

28840890 is a wasteful number, since it uses less digits than its factorization.

28840890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73974.

The product of its (nonzero) digits is 36864, while the sum is 39.

The square root of 28840890 is about 5370.3714955299. The cubic root of 28840890 is about 306.6687709896.

The spelling of 28840890 in words is "twenty-eight million, eight hundred forty thousand, eight hundred ninety".