28783225 has 27 divisors (see below), whose sum is σ = 37990407. Its totient is φ = 21631680.

The previous prime is 28783219. The next prime is 28783301. The reversal of 28783225 is 52238782.

The square root of 28783225 is 5365.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 5396329 + 23386896 = 2323^2 + 4836^2 .

It is not a de Polignac number, because 28783225 - 2³ = 28783217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 777907 + ... + 777943.

Almost surely, 2^28783225 is an apocalyptic number.

28783225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28783225 is the 5365-th square number.

28783225 is the 2683-rd centered octagonal number.

It is an amenable number.

28783225 is a deficient number, since it is larger than the sum of its proper divisors (9207182).

28783225 is an equidigital number, since it uses as much as digits as its factorization.

28783225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 71 counting only the distinct ones).

The product of its digits is 53760, while the sum is 37.

The cubic root of 28783225 is about 306.4642482474.

The spelling of 28783225 in words is "twenty-eight million, seven hundred eighty-three thousand, two hundred twenty-five".