666645835 has 8 divisors (see below), whose sum is σ = 821596176. Its totient is φ = 518902560.

The previous prime is 666645829. The next prime is 666645851. The reversal of 666645835 is 538546666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 666645835 - 2¹⁵ = 666613067 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 (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1801561 + ... + 1801930.

It is an arithmetic number, because the mean of its divisors is an integer number (102699522).

Almost surely, 2^666645835 is an apocalyptic number.

666645835 is a deficient number, since it is larger than the sum of its proper divisors (154950341).

666645835 is a wasteful number, since it uses less digits than its factorization.

666645835 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3603533.

The product of its digits is 3110400, while the sum is 49.

The square root of 666645835 is about 25819.4855680744. The cubic root of 666645835 is about 873.5713655730.

The spelling of 666645835 in words is "six hundred sixty-six million, six hundred forty-five thousand, eight hundred thirty-five".