667993 has 4 divisors (see below), whose sum is σ = 671140. Its totient is φ = 664848.

The previous prime is 667991. The next prime is 667999. The reversal of 667993 is 399766.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 652864 + 15129 = 808^2 + 123^2 .

It is a cyclic number.

It is not a de Polignac number, because 667993 - 2¹ = 667991 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667991) 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, 1230 + ... + 1687.

It is an arithmetic number, because the mean of its divisors is an integer number (167785).

2⁶⁶⁷⁹⁹³ is an apocalyptic number.

It is an amenable number.

667993 is a deficient number, since it is larger than the sum of its proper divisors (3147).

667993 is a wasteful number, since it uses less digits than its factorization.

667993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3146.

The product of its digits is 61236, while the sum is 40.

The square root of 667993 is about 817.3083873300. The cubic root of 667993 is about 87.4159410413.

The spelling of 667993 in words is "six hundred sixty-seven thousand, nine hundred ninety-three".