28480440 has 128 divisors (see below), whose sum is σ = 94556160. Its totient is φ = 6825984.

The previous prime is 28480429. The next prime is 28480469. The reversal of 28480440 is 4408482.

It is a super-2 number, since 2×28480440² = 1622270925187200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 28480398 and 28480407.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 46617 + ... + 47223.

It is an arithmetic number, because the mean of its divisors is an integer number (738720).

Almost surely, 2^28480440 is an apocalyptic number.

28480440 is a gapful number since it is divisible by the number (20) 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 28480440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47278080).

28480440 is an abundant number, since it is smaller than the sum of its proper divisors (66075720).

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

28480440 is a wasteful number, since it uses less digits than its factorization.

28480440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 657 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 30.

The square root of 28480440 is about 5336.7068497342. The cubic root of 28480440 is about 305.3858415234.

It can be divided in two parts, 28480 and 440, that added together give a triangular number (28920 = T₂₄₀).

The spelling of 28480440 in words is "twenty-eight million, four hundred eighty thousand, four hundred forty".