28121560 has 16 divisors (see below), whose sum is σ = 63273600. Its totient is φ = 11248608.

The previous prime is 28121521. The next prime is 28121581. The reversal of 28121560 is 6512182.

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 3 ways as a sum of consecutive naturals, for example, 351480 + ... + 351559.

It is an arithmetic number, because the mean of its divisors is an integer number (3954600).

Almost surely, 2^28121560 is an apocalyptic number.

28121560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28121560 is an abundant number, since it is smaller than the sum of its proper divisors (35152040).

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

28121560 is a wasteful number, since it uses less digits than its factorization.

28121560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703050 (or 703046 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 28121560 is about 5302.9765226710. The cubic root of 28121560 is about 304.0977005917.

The spelling of 28121560 in words is "twenty-eight million, one hundred twenty-one thousand, five hundred sixty".