28017738225 has 27 divisors (see below), whose sum is σ = 50187379723. Its totient is φ = 14941454640.

The previous prime is 28017738223. The next prime is 28017738251. The reversal of 28017738225 is 52283771082.

The square root of 28017738225 is 167385.

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

28017738225 is a `hidden beast` number, since 2 + 80 + 177 + 382 + 25 = 666.

It can be written as a sum of positive squares in only one way, i.e., 10086385761 + 17931352464 = 100431^2 + 133908^2 .

It is not a de Polignac number, because 28017738225 - 2¹ = 28017738223 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28017738223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2505196 + ... + 2516354.

Almost surely, 2^28017738225 is an apocalyptic number.

28017738225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28017738225 is the 167385-th square number.

28017738225 is the 83693-rd centered octagonal number.

It is an amenable number.

28017738225 is a deficient number, since it is larger than the sum of its proper divisors (22169641498).

28017738225 is an frugal number, since it uses more digits than its factorization.

28017738225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22334 (or 11167 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 28017738225 in words is "twenty-eight billion, seventeen million, seven hundred thirty-eight thousand, two hundred twenty-five".