667746756 has 18 divisors (see below), whose sum is σ = 1687915502. Its totient is φ = 222582240.

The previous prime is 667746749. The next prime is 667746769. The reversal of 667746756 is 657647766.

667746756 is a `hidden beast` number, since 66 + 77 + 467 + 56 = 666.

It can be written as a sum of positive squares in only one way, i.e., 525326400 + 142420356 = 22920^2 + 11934^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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 5 ways as a sum of consecutive naturals, for example, 9274225 + ... + 9274296.

Almost surely, 2^667746756 is an apocalyptic number.

It is an amenable number.

667746756 is an abundant number, since it is smaller than the sum of its proper divisors (1020168746).

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

667746756 is a wasteful number, since it uses less digits than its factorization.

667746756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18548531 (or 18548526 counting only the distinct ones).

The product of its digits is 8890560, while the sum is 54.

The square root of 667746756 is about 25840.7963499579. The cubic root of 667746756 is about 874.0519826580.

The spelling of 667746756 in words is "six hundred sixty-seven million, seven hundred forty-six thousand, seven hundred fifty-six".