668552019 has 4 divisors (see below), whose sum is σ = 891402696. Its totient is φ = 445701344.

The previous prime is 668551999. The next prime is 668552021. The reversal of 668552019 is 910255866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 668552019 - 2⁵ = 668551987 is a prime.

It is a super-2 number, since 2×668552019² = 893923604217952722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668552029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111425334 + ... + 111425339.

It is an arithmetic number, because the mean of its divisors is an integer number (222850674).

Almost surely, 2^668552019 is an apocalyptic number.

668552019 is a deficient number, since it is larger than the sum of its proper divisors (222850677).

668552019 is a wasteful number, since it uses less digits than its factorization.

668552019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222850676.

The product of its (nonzero) digits is 129600, while the sum is 42.

The square root of 668552019 is about 25856.3728894832. The cubic root of 668552019 is about 874.4031931403.

The spelling of 668552019 in words is "six hundred sixty-eight million, five hundred fifty-two thousand, nineteen".