999225 has 18 divisors (see below), whose sum is σ = 1790126. Its totient is φ = 532800.

The previous prime is 999221. The next prime is 999233. The reversal of 999225 is 522999.

It can be written as a sum of positive squares in 3 ways, for example, as 36864 + 962361 = 192^2 + 981^2 .

It is not a de Polignac number, because 999225 - 2² = 999221 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 999225.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999225.

It is not an unprimeable number, because it can be changed into a prime (999221) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1996 + ... + 2445.

2⁹⁹⁹²²⁵ is an apocalyptic number.

It is an amenable number.

999225 is a deficient number, since it is larger than the sum of its proper divisors (790901).

999225 is a wasteful number, since it uses less digits than its factorization.

999225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4457 (or 4449 counting only the distinct ones).

The product of its digits is 14580, while the sum is 36.

The square root of 999225 is about 999.6124248928. The cubic root of 999225 is about 99.9741599902.

It can be divided in two parts, 9 and 99225, that multiplied together give a square (893025 = 945²).

The spelling of 999225 in words is "nine hundred ninety-nine thousand, two hundred twenty-five".