28909144 has 16 divisors (see below), whose sum is σ = 59132520. Its totient is φ = 13140480.

The previous prime is 28909123. The next prime is 28909147. The reversal of 28909144 is 44190982.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28909147) 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, 164169 + ... + 164344.

Almost surely, 2^28909144 is an apocalyptic number.

It is an amenable number.

28909144 is an abundant number, since it is smaller than the sum of its proper divisors (30223376).

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

28909144 is a wasteful number, since it uses less digits than its factorization.

28909144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328530 (or 328526 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 28909144 is about 5376.7224216989. The cubic root of 28909144 is about 306.9104981590.

The spelling of 28909144 in words is "twenty-eight million, nine hundred nine thousand, one hundred forty-four".