668405213 has 16 divisors (see below), whose sum is σ = 773450496. Its totient is φ = 565781760.

The previous prime is 668405203. The next prime is 668405263. The reversal of 668405213 is 312504866.

It is a cyclic number.

It is not a de Polignac number, because 668405213 - 2¹⁰ = 668404189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668405203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 311123 + ... + 313263.

It is an arithmetic number, because the mean of its divisors is an integer number (48340656).

Almost surely, 2^668405213 is an apocalyptic number.

It is an amenable number.

668405213 is a deficient number, since it is larger than the sum of its proper divisors (105045283).

668405213 is a wasteful number, since it uses less digits than its factorization.

668405213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2684.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 668405213 is about 25853.5338590298. The cubic root of 668405213 is about 874.3391856392.

The spelling of 668405213 in words is "six hundred sixty-eight million, four hundred five thousand, two hundred thirteen".