667969 has 4 divisors (see below), whose sum is σ = 673200. Its totient is φ = 662740.

The previous prime is 667963. The next prime is 667987. The reversal of 667969 is 969766.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 667969 - 2¹¹ = 665921 is a prime.

It is a super-2 number, since 2×667969² = 892365169922, which contains 22 as substring.

It is a Duffinian number.

667969 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (667963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2419 + ... + 2680.

It is an arithmetic number, because the mean of its divisors is an integer number (168300).

2⁶⁶⁷⁹⁶⁹ is an apocalyptic number.

It is an amenable number.

667969 is a deficient number, since it is larger than the sum of its proper divisors (5231).

667969 is a wasteful number, since it uses less digits than its factorization.

667969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5230.

The product of its digits is 122472, while the sum is 43.

The square root of 667969 is about 817.2937048577. The cubic root of 667969 is about 87.4148941203.

The spelling of 667969 in words is "six hundred sixty-seven thousand, nine hundred sixty-nine".