28866856 has 8 divisors (see below), whose sum is σ = 54125370. Its totient is φ = 14433424.

The previous prime is 28866853. The next prime is 28866881. The reversal of 28866856 is 65866882.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 28793956 + 72900 = 5366^2 + 270^2 .

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

It is not an unprimeable number, because it can be changed into a prime (28866853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1804171 + ... + 1804186.

Almost surely, 2^28866856 is an apocalyptic number.

It is an amenable number.

28866856 is a deficient number, since it is larger than the sum of its proper divisors (25258514).

28866856 is a wasteful number, since it uses less digits than its factorization.

28866856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3608363 (or 3608359 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 49.

The square root of 28866856 is about 5372.7884752705. The cubic root of 28866856 is about 306.7607766196.

The spelling of 28866856 in words is "twenty-eight million, eight hundred sixty-six thousand, eight hundred fifty-six".