6667691 has 4 divisors (see below), whose sum is σ = 6715800. Its totient is φ = 6619584.

The previous prime is 6667673. The next prime is 6667693. The reversal of 6667691 is 1967666.

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 6667691 - 2¹⁸ = 6405547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6667693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23846 + ... + 24123.

It is an arithmetic number, because the mean of its divisors is an integer number (1678950).

Almost surely, 2^6667691 is an apocalyptic number.

6667691 is a deficient number, since it is larger than the sum of its proper divisors (48109).

6667691 is a wasteful number, since it uses less digits than its factorization.

6667691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48108.

The product of its digits is 81648, while the sum is 41.

The square root of 6667691 is about 2582.1872511497. The cubic root of 6667691 is about 188.2168446283.

The spelling of 6667691 in words is "six million, six hundred sixty-seven thousand, six hundred ninety-one".