28921760 has 192 divisors, whose sum is σ = 87091200. Its totient is φ = 9031680.

The previous prime is 28921727. The next prime is 28921771. The reversal of 28921760 is 6712982.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 28921760.

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, 932945 + ... + 932975.

It is an arithmetic number, because the mean of its divisors is an integer number (453600).

Almost surely, 2^28921760 is an apocalyptic number.

28921760 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 28921760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43545600).

28921760 is an abundant number, since it is smaller than the sum of its proper divisors (58169440).

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

28921760 is a wasteful number, since it uses less digits than its factorization.

28921760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 62 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 28921760 is about 5377.8954991707. The cubic root of 28921760 is about 306.9551370887.

The spelling of 28921760 in words is "twenty-eight million, nine hundred twenty-one thousand, seven hundred sixty".