28089928 has 8 divisors (see below), whose sum is σ = 52668630. Its totient is φ = 14044960.

The previous prime is 28089917. The next prime is 28089931. The reversal of 28089928 is 82998082.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 26234884 + 1855044 = 5122^2 + 1362^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1755613 + ... + 1755628.

Almost surely, 2^28089928 is an apocalyptic number.

It is an amenable number.

28089928 is a deficient number, since it is larger than the sum of its proper divisors (24578702).

28089928 is a wasteful number, since it uses less digits than its factorization.

28089928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3511247 (or 3511243 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 46.

The square root of 28089928 is about 5299.9932075428. The cubic root of 28089928 is about 303.9836383161.

The spelling of 28089928 in words is "twenty-eight million, eighty-nine thousand, nine hundred twenty-eight".