666898798 has 4 divisors (see below), whose sum is σ = 1000348200. Its totient is φ = 333449398.

The previous prime is 666898789. The next prime is 666898801. The reversal of 666898798 is 897898666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166724698 + ... + 166724701.

It is an arithmetic number, because the mean of its divisors is an integer number (250087050).

Almost surely, 2^666898798 is an apocalyptic number.

666898798 is a deficient number, since it is larger than the sum of its proper divisors (333449402).

666898798 is a wasteful number, since it uses less digits than its factorization.

666898798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333449401.

The product of its digits is 62705664, while the sum is 67.

The square root of 666898798 is about 25824.3837874208. The cubic root of 666898798 is about 873.6818456694.

The spelling of 666898798 in words is "six hundred sixty-six million, eight hundred ninety-eight thousand, seven hundred ninety-eight".