668944155 has 16 divisors (see below), whose sum is σ = 1167611904. Its totient is φ = 324336480.

The previous prime is 668944139. The next prime is 668944193. The reversal of 668944155 is 551449866.

It is not a de Polignac number, because 668944155 - 2⁴ = 668944139 is a prime.

It is an unprimeable number.

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, 2026939 + ... + 2027268.

It is an arithmetic number, because the mean of its divisors is an integer number (72975744).

Almost surely, 2^668944155 is an apocalyptic number.

668944155 is a deficient number, since it is larger than the sum of its proper divisors (498667749).

668944155 is a wasteful number, since it uses less digits than its factorization.

668944155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4054226.

The product of its digits is 1036800, while the sum is 48.

The square root of 668944155 is about 25863.9547440062. The cubic root of 668944155 is about 874.5741187345.

The spelling of 668944155 in words is "six hundred sixty-eight million, nine hundred forty-four thousand, one hundred fifty-five".