16664225 has 12 divisors (see below), whose sum is σ = 20788476. Its totient is φ = 13250880.

The previous prime is 16664203. The next prime is 16664231. The reversal of 16664225 is 52246661.

It can be written as a sum of positive squares in 6 ways, for example, as 3055504 + 13608721 = 1748^2 + 3689^2 .

It is not a de Polignac number, because 16664225 - 2⁶ = 16664161 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16664191 and 16664200.

It is a congruent 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 11 ways as a sum of consecutive naturals, for example, 2399 + ... + 6251.

It is an arithmetic number, because the mean of its divisors is an integer number (1732373).

Almost surely, 2^16664225 is an apocalyptic number.

It is an amenable number.

16664225 is a deficient number, since it is larger than the sum of its proper divisors (4124251).

16664225 is a wasteful number, since it uses less digits than its factorization.

16664225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4036 (or 4031 counting only the distinct ones).

The product of its digits is 17280, while the sum is 32.

The square root of 16664225 is about 4082.1838518127. The cubic root of 16664225 is about 255.4240030407.

It can be divided in two parts, 16 and 664225, that multiplied together give a square (10627600 = 3260²).

The spelling of 16664225 in words is "sixteen million, six hundred sixty-four thousand, two hundred twenty-five".