668413 has 4 divisors (see below), whose sum is σ = 671328. Its totient is φ = 665500.

The previous prime is 668407. The next prime is 668417. The reversal of 668413 is 314866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 314866 = 2 ⋅157433.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668413 is a prime.

It is a Duffinian 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.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1081 + ... + 1582.

It is an arithmetic number, because the mean of its divisors is an integer number (167832).

2⁶⁶⁸⁴¹³ is an apocalyptic number.

It is an amenable number.

668413 is a deficient number, since it is larger than the sum of its proper divisors (2915).

668413 is a wasteful number, since it uses less digits than its factorization.

668413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914.

The product of its digits is 3456, while the sum is 28.

The square root of 668413 is about 817.5652879128. The cubic root of 668413 is about 87.4342581011.

It can be divided in two parts, 668 and 413, that added together give a triangular number (1081 = T₄₆).

The spelling of 668413 in words is "six hundred sixty-eight thousand, four hundred thirteen".