28120500 has 96 divisors (see below), whose sum is σ = 91029120. Its totient is φ = 7495200.

The previous prime is 28120487. The next prime is 28120511. The reversal of 28120500 is 502182.

It is a Harshad number since it is a multiple of its sum of digits (18).

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, 12459 + ... + 14541.

It is an arithmetic number, because the mean of its divisors is an integer number (948220).

Almost surely, 2^28120500 is an apocalyptic number.

28120500 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 28120500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45514560).

28120500 is an abundant number, since it is smaller than the sum of its proper divisors (62908620).

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

28120500 is a wasteful number, since it uses less digits than its factorization.

28120500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2111 (or 2093 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 28120500 is about 5302.8765778585. The cubic root of 28120500 is about 304.0938797082.

Adding to 28120500 its reverse (502182), we get a palindrome (28622682).

The spelling of 28120500 in words is "twenty-eight million, one hundred twenty thousand, five hundred".