668046551 has 2 divisors, whose sum is σ = 668046552. Its totient is φ = 668046550.

The previous prime is 668046539. The next prime is 668046629. The reversal of 668046551 is 155640866.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668046551 - 2⁶ = 668046487 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 668046499 and 668046508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667046551) 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 as a sum of consecutive naturals, namely, 334023275 + 334023276.

It is an arithmetic number, because the mean of its divisors is an integer number (334023276).

Almost surely, 2^668046551 is an apocalyptic number.

668046551 is a deficient number, since it is larger than the sum of its proper divisors (1).

668046551 is an equidigital number, since it uses as much as digits as its factorization.

668046551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 668046551 is about 25846.5965070839. The cubic root of 668046551 is about 874.1827693705.

The spelling of 668046551 in words is "six hundred sixty-eight million, forty-six thousand, five hundred fifty-one".