666225523 has 4 divisors (see below), whose sum is σ = 682474968. Its totient is φ = 649976080.

The previous prime is 666225509. The next prime is 666225559. The reversal of 666225523 is 325522666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 666225523 - 2⁹ = 666225011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666225583) 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 3 ways as a sum of consecutive naturals, for example, 8124661 + ... + 8124742.

It is an arithmetic number, because the mean of its divisors is an integer number (170618742).

Almost surely, 2^666225523 is an apocalyptic number.

666225523 is a deficient number, since it is larger than the sum of its proper divisors (16249445).

666225523 is a wasteful number, since it uses less digits than its factorization.

666225523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16249444.

The product of its digits is 129600, while the sum is 37.

The square root of 666225523 is about 25811.3448506660. The cubic root of 666225523 is about 873.3877349746.

The spelling of 666225523 in words is "six hundred sixty-six million, two hundred twenty-five thousand, five hundred twenty-three".