28015730 has 8 divisors (see below), whose sum is σ = 50428332. Its totient is φ = 11206288.

The previous prime is 28015717. The next prime is 28015777. The reversal of 28015730 is 3751082.

It can be written as a sum of positive squares in 2 ways, for example, as 24492601 + 3523129 = 4949^2 + 1877^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×28015730² = 1569762254865800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28015730.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1400777 + ... + 1400796.

Almost surely, 2^28015730 is an apocalyptic number.

28015730 is a deficient number, since it is larger than the sum of its proper divisors (22412602).

28015730 is a wasteful number, since it uses less digits than its factorization.

28015730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2801580.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 28015730 is about 5292.9887587260. The cubic root of 28015730 is about 303.7157502860.

The spelling of 28015730 in words is "twenty-eight million, fifteen thousand, seven hundred thirty".