667798 has 8 divisors (see below), whose sum is σ = 1005480. Its totient is φ = 332640.

The previous prime is 667781. The next prime is 667801. The reversal of 667798 is 897766.

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

It is a congruent number.

It is an unprimeable number.

667798 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318 + ... + 1198.

It is an arithmetic number, because the mean of its divisors is an integer number (125685).

2⁶⁶⁷⁷⁹⁸ is an apocalyptic number.

667798 is a deficient number, since it is larger than the sum of its proper divisors (337682).

667798 is a wasteful number, since it uses less digits than its factorization.

667798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262.

The product of its digits is 127008, while the sum is 43.

The square root of 667798 is about 817.1890846065. The cubic root of 667798 is about 87.4074340822.

The spelling of 667798 in words is "six hundred sixty-seven thousand, seven hundred ninety-eight".