28784690 has 24 divisors (see below), whose sum is σ = 56953260. Its totient is φ = 10466720.

The previous prime is 28784683. The next prime is 28784711. The reversal of 28784690 is 9648782.

It can be written as a sum of positive squares in 2 ways, for example, as 27071209 + 1713481 = 5203^2 + 1309^2 .

It is a super-2 number, since 2×28784690² = 1657116756792200, which contains 22 as substring.

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 in 11 ways as a sum of consecutive naturals, for example, 10685 + ... + 13104.

Almost surely, 2^28784690 is an apocalyptic number.

28784690 is a deficient number, since it is larger than the sum of its proper divisors (28168570).

28784690 is a wasteful number, since it uses less digits than its factorization.

28784690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23818 (or 23807 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 28784690 is about 5365.1365313475. The cubic root of 28784690 is about 306.4694476011.

The spelling of 28784690 in words is "twenty-eight million, seven hundred eighty-four thousand, six hundred ninety".