668412 has 30 divisors (see below), whose sum is σ = 1748208. Its totient is φ = 222696.

The previous prime is 668407. The next prime is 668417. The reversal of 668412 is 214866.

It is an interprime number because it is at equal distance from previous prime (668407) and next prime (668417).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668417) by changing a digit.

668412 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 9 ways as a sum of consecutive naturals, for example, 708 + ... + 1355.

2⁶⁶⁸⁴¹² is an apocalyptic number.

It is an amenable number.

668412 is an abundant number, since it is smaller than the sum of its proper divisors (1079796).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

668412 is a wasteful number, since it uses less digits than its factorization.

668412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2079 (or 2068 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 668412 is about 817.5646763407. The cubic root of 668412 is about 87.4342144982.

It can be divided in two parts, 6684 and 12, that multiplied together give a palindrome (80208).

The spelling of 668412 in words is "six hundred sixty-eight thousand, four hundred twelve".