668149873 has 2 divisors, whose sum is σ = 668149874. Its totient is φ = 668149872.

The previous prime is 668149849. The next prime is 668149919. The reversal of 668149873 is 378941866.

It is a happy number.

668149873 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 533055744 + 135094129 = 23088^2 + 11623^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668149873 is a prime.

It is a super-2 number, since 2×668149873² = 892848505579832258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 668149873.

It is not a weakly prime, because it can be changed into another prime (668149813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334074936 + 334074937.

It is an arithmetic number, because the mean of its divisors is an integer number (334074937).

Almost surely, 2^668149873 is an apocalyptic number.

It is an amenable number.

668149873 is a deficient number, since it is larger than the sum of its proper divisors (1).

668149873 is an equidigital number, since it uses as much as digits as its factorization.

668149873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1741824, while the sum is 52.

The square root of 668149873 is about 25848.5951842649. The cubic root of 668149873 is about 874.2278349206.

The spelling of 668149873 in words is "six hundred sixty-eight million, one hundred forty-nine thousand, eight hundred seventy-three".