16281225 has 27 divisors (see below), whose sum is σ = 29270293.
Its totient is φ = 8651040.
The previous prime is 16281191. The next prime is 16281247. The reversal of 16281225 is 52218261.
It is a happy number.
The square root of 16281225 is 4035.
It is a perfect power (a square), and thus also a powerful number.
16281225 is a `hidden beast` number, since 1 + 628 + 12 + 25 = 666.
It can be written as a sum of positive squares in 4 ways, for example, as 6245001 + 10036224 = 2499^2 + 3168^2
It is not a de Polignac number, because 16281225 - 215 = 16248457 is a prime.
It is a Duffinian number.
It is an unprimeable number.
It is a pernicious number, because its binary representation contains a prime number (13) of ones.
It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 60391 + ... + 60659.
Almost surely, 216281225 is an apocalyptic number.
16281225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.
16281225 is the 4035-th square number.
16281225 is the 2018-th centered octagonal number.
It is an amenable number.
16281225 is a deficient number, since it is larger than the sum of its proper divisors (12989068).
16281225 is an equidigital number, since it uses as much as digits as its factorization.
16281225 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 554 (or 277 counting only the distinct ones).
The product of its digits is 1920, while the sum is 27.
The cubic root of 16281225 is about 253.4519825488.
Adding to 16281225 its reverse (52218261), we get a palindrome (68499486).
The spelling of 16281225 in words is "sixteen million, two hundred eighty-one thousand, two hundred twenty-five".