666825 has 24 divisors (see below), whose sum is σ = 1169568. Its totient is φ = 334080.

The previous prime is 666823. The next prime is 666829. The reversal of 666825 is 528666.

It is not a de Polignac number, because 666825 - 2¹ = 666823 is a prime.

It is not an unprimeable number, because it can be changed into a prime (666821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1014 + ... + 1536.

It is an arithmetic number, because the mean of its divisors is an integer number (48732).

2⁶⁶⁶⁸²⁵ is an apocalyptic number.

It is an amenable number.

666825 is a deficient number, since it is larger than the sum of its proper divisors (502743).

666825 is a wasteful number, since it uses less digits than its factorization.

666825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553 (or 548 counting only the distinct ones).

The product of its digits is 17280, while the sum is 33.

The square root of 666825 is about 816.5935341405. The cubic root of 666825 is about 87.3649617715.

The spelling of 666825 in words is "six hundred sixty-six thousand, eight hundred twenty-five".