28991048 has 8 divisors (see below), whose sum is σ = 54358230. Its totient is φ = 14495520.

The previous prime is 28991041. The next prime is 28991071. The reversal of 28991048 is 84019982.

It can be written as a sum of positive squares in only one way, i.e., 28111204 + 879844 = 5302^2 + 938^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 28990996 and 28991014.

It is not an unprimeable number, because it can be changed into a prime (28991041) 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 as a sum of consecutive naturals, namely, 1811933 + ... + 1811948.

Almost surely, 2^28991048 is an apocalyptic number.

It is an amenable number.

28991048 is a deficient number, since it is larger than the sum of its proper divisors (25367182).

28991048 is a wasteful number, since it uses less digits than its factorization.

28991048 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3623887 (or 3623883 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 28991048 is about 5384.3335706473. Note that the first 3 decimals coincide. The cubic root of 28991048 is about 307.2000662344.

The spelling of 28991048 in words is "twenty-eight million, nine hundred ninety-one thousand, forty-eight".