666873684 has 36 divisors (see below), whose sum is σ = 1759002336. Its totient is φ = 212626128.

The previous prime is 666873679. The next prime is 666873703. The reversal of 666873684 is 486378666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 666873684.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 401874 + ... + 403529.

It is an arithmetic number, because the mean of its divisors is an integer number (48861176).

Almost surely, 2^666873684 is an apocalyptic number.

It is an amenable number.

666873684 is an abundant number, since it is smaller than the sum of its proper divisors (1092128652).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666873684 is a wasteful number, since it uses less digits than its factorization.

666873684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805436 (or 805431 counting only the distinct ones).

The product of its digits is 6967296, while the sum is 54.

The square root of 666873684 is about 25823.8975369714. The cubic root of 666873684 is about 873.6708785275.

It can be divided in two parts, 6 and 66873684, that multiplied together give a palindrome (401242104).

The spelling of 666873684 in words is "six hundred sixty-six million, eight hundred seventy-three thousand, six hundred eighty-four".