667121 has 8 divisors (see below), whose sum is σ = 821184. Its totient is φ = 527760.

The previous prime is 667103. The next prime is 667123. The reversal of 667121 is 121766.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 667121 - 2¹⁸ = 404977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (667123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3575 + ... + 3756.

It is an arithmetic number, because the mean of its divisors is an integer number (102648).

2⁶⁶⁷¹²¹ is an apocalyptic number.

It is an amenable number.

667121 is a deficient number, since it is larger than the sum of its proper divisors (154063).

667121 is a wasteful number, since it uses less digits than its factorization.

667121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7351.

The product of its digits is 504, while the sum is 23.

The square root of 667121 is about 816.7747547519. The cubic root of 667121 is about 87.3778868035.

Adding to 667121 its reverse (121766), we get a palindrome (788887).

The spelling of 667121 in words is "six hundred sixty-seven thousand, one hundred twenty-one".