28893440 has 36 divisors (see below), whose sum is σ = 69211884. Its totient is φ = 11556864.

The previous prime is 28893419. The next prime is 28893461. The reversal of 28893440 is 4439882.

It is an interprime number because it is at equal distance from previous prime (28893419) and next prime (28893461).

It can be written as a sum of positive squares in 2 ways, for example, as 5234944 + 23658496 = 2288^2 + 4864^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28893394 and 28893403.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10007 + ... + 12566.

Almost surely, 2^28893440 is an apocalyptic number.

28893440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28893440 is an abundant number, since it is smaller than the sum of its proper divisors (40318444).

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

28893440 is an equidigital number, since it uses as much as digits as its factorization.

28893440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22594 (or 22580 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 38.

The square root of 28893440 is about 5375.2618540867. The cubic root of 28893440 is about 306.8549148754.

The spelling of 28893440 in words is "twenty-eight million, eight hundred ninety-three thousand, four hundred forty".