668698 has 4 divisors (see below), whose sum is σ = 1003050. Its totient is φ = 334348.

The previous prime is 668687. The next prime is 668699. The reversal of 668698 is 896866.

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

It can be written as a sum of positive squares in only one way, i.e., 635209 + 33489 = 797^2 + 183^2 .

It is not an unprimeable number, because it can be changed into a prime (668699) by changing a digit.

668698 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 as a sum of consecutive naturals, namely, 167173 + ... + 167176.

2⁶⁶⁸⁶⁹⁸ is an apocalyptic number.

668698 is a deficient number, since it is larger than the sum of its proper divisors (334352).

668698 is a wasteful number, since it uses less digits than its factorization.

668698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334351.

The product of its digits is 124416, while the sum is 43.

The square root of 668698 is about 817.7395673440. The cubic root of 668698 is about 87.4466831650.

The spelling of 668698 in words is "six hundred sixty-eight thousand, six hundred ninety-eight".