28908440 has 32 divisors (see below), whose sum is σ = 70958160. Its totient is φ = 10512000.

The previous prime is 28908421. The next prime is 28908469. The reversal of 28908440 is 4480982.

It is a self number, because there is not a number n which added to its sum of digits gives 28908440.

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 7 ways as a sum of consecutive naturals, for example, 32411 + ... + 33290.

Almost surely, 2^28908440 is an apocalyptic number.

28908440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28908440 is an abundant number, since it is smaller than the sum of its proper divisors (42049720).

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

28908440 is a wasteful number, since it uses less digits than its factorization.

28908440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65723 (or 65719 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 35.

The square root of 28908440 is about 5376.6569539073. The cubic root of 28908440 is about 306.9080068280.

The spelling of 28908440 in words is "twenty-eight million, nine hundred eight thousand, four hundred forty".