28772273 has 6 divisors (see below), whose sum is σ = 29572326. Its totient is φ = 27993312.

The previous prime is 28772257. The next prime is 28772299. The reversal of 28772273 is 37227782.

28772273 is nontrivially palindromic in base 16.

It can be written as a sum of positive squares in 3 ways, for example, as 5895184 + 22877089 = 2428^2 + 4783^2 .

It is not a de Polignac number, because 28772273 - 2⁴ = 28772257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28772873) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9140 + ... + 11877.

It is an arithmetic number, because the mean of its divisors is an integer number (4928721).

Almost surely, 2^28772273 is an apocalyptic number.

It is an amenable number.

28772273 is a deficient number, since it is larger than the sum of its proper divisors (800053).

28772273 is an equidigital number, since it uses as much as digits as its factorization.

28772273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21091 (or 21054 counting only the distinct ones).

The product of its digits is 65856, while the sum is 38.

The square root of 28772273 is about 5363.9792132334. The cubic root of 28772273 is about 306.4253734949.

The spelling of 28772273 in words is "twenty-eight million, seven hundred seventy-two thousand, two hundred seventy-three".