668910751 has 4 divisors (see below), whose sum is σ = 704116600. Its totient is φ = 633704904.

The previous prime is 668910743. The next prime is 668910757. The reversal of 668910751 is 157019866.

It is a happy number.

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 668910751 - 2³ = 668910743 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 668910698 and 668910707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668910757) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 17602896 + ... + 17602933.

It is an arithmetic number, because the mean of its divisors is an integer number (176029150).

Almost surely, 2^668910751 is an apocalyptic number.

668910751 is a deficient number, since it is larger than the sum of its proper divisors (35205849).

668910751 is a wasteful number, since it uses less digits than its factorization.

668910751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35205848.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 668910751 is about 25863.3089723647. The cubic root of 668910751 is about 874.5595610867.

The spelling of 668910751 in words is "six hundred sixty-eight million, nine hundred ten thousand, seven hundred fifty-one".