28272730 has 16 divisors (see below), whose sum is σ = 50978664. Its totient is φ = 11289600.

The previous prime is 28272721. The next prime is 28272731. The reversal of 28272730 is 3727282.

It can be written as a sum of positive squares in 4 ways, for example, as 13039321 + 15233409 = 3611^2 + 3903^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28272692 and 28272701.

It is not an unprimeable number, because it can be changed into a prime (28272731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4630 + ... + 8830.

Almost surely, 2^28272730 is an apocalyptic number.

28272730 is a deficient number, since it is larger than the sum of its proper divisors (22705934).

28272730 is a wasteful number, since it uses less digits than its factorization.

28272730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4881.

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 28272730 is about 5317.2107349625. The cubic root of 28272730 is about 304.6416287113.

The spelling of 28272730 in words is "twenty-eight million, two hundred seventy-two thousand, seven hundred thirty".