28866388 has 6 divisors (see below), whose sum is σ = 50516186. Its totient is φ = 14433192.

The previous prime is 28866379. The next prime is 28866389. The reversal of 28866388 is 88366882.

It can be written as a sum of positive squares in only one way, i.e., 23794884 + 5071504 = 4878^2 + 2252^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28866389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3608295 + ... + 3608302.

Almost surely, 2^28866388 is an apocalyptic number.

It is an amenable number.

28866388 is a deficient number, since it is larger than the sum of its proper divisors (21649798).

28866388 is a wasteful number, since it uses less digits than its factorization.

28866388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7216601 (or 7216599 counting only the distinct ones).

The product of its digits is 884736, while the sum is 49.

The square root of 28866388 is about 5372.7449222907. The cubic root of 28866388 is about 306.7591188381.

The spelling of 28866388 in words is "twenty-eight million, eight hundred sixty-six thousand, three hundred eighty-eight".