28978856 has 8 divisors (see below), whose sum is σ = 54335370. Its totient is φ = 14489424.

The previous prime is 28978823. The next prime is 28978867. The reversal of 28978856 is 65887982.

It can be written as a sum of positive squares in only one way, i.e., 28793956 + 184900 = 5366^2 + 430^2 .

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 = 28978798 and 28978807.

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 as a sum of consecutive naturals, namely, 1811171 + ... + 1811186.

Almost surely, 2^28978856 is an apocalyptic number.

It is an amenable number.

28978856 is a deficient number, since it is larger than the sum of its proper divisors (25356514).

28978856 is a wasteful number, since it uses less digits than its factorization.

28978856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3622363 (or 3622359 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 53.

The square root of 28978856 is about 5383.2012780501. The cubic root of 28978856 is about 307.1569965213.

The spelling of 28978856 in words is "twenty-eight million, nine hundred seventy-eight thousand, eight hundred fifty-six".