667986664 has 8 divisors (see below), whose sum is σ = 1252475010. Its totient is φ = 333993328.

The previous prime is 667986653. The next prime is 667986707. The reversal of 667986664 is 466689766.

667986664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 662650564 + 5336100 = 25742^2 + 2310^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 667986599 and 667986608.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41749159 + ... + 41749174.

Almost surely, 2^667986664 is an apocalyptic number.

It is an amenable number.

667986664 is a deficient number, since it is larger than the sum of its proper divisors (584488346).

667986664 is a wasteful number, since it uses less digits than its factorization.

667986664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83498339 (or 83498335 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 58.

The square root of 667986664 is about 25845.4379726868. The cubic root of 667986664 is about 874.1566465662.

The spelling of 667986664 in words is "six hundred sixty-seven million, nine hundred eighty-six thousand, six hundred sixty-four".