668043555 has 16 divisors (see below), whose sum is σ = 1069264800. Its totient is φ = 356158208.

The previous prime is 668043529. The next prime is 668043569. The reversal of 668043555 is 555340866.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 668043555 - 2¹³ = 668035363 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44671 + ... + 57719.

It is an arithmetic number, because the mean of its divisors is an integer number (66829050).

Almost surely, 2^668043555 is an apocalyptic number.

668043555 is a deficient number, since it is larger than the sum of its proper divisors (401221245).

668043555 is a wasteful number, since it uses less digits than its factorization.

668043555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16470.

The product of its (nonzero) digits is 432000, while the sum is 42.

The square root of 668043555 is about 25846.5385496782. The cubic root of 668043555 is about 874.1814625476.

The spelling of 668043555 in words is "six hundred sixty-eight million, forty-three thousand, five hundred fifty-five".