668692523 has 2 divisors, whose sum is σ = 668692524. Its totient is φ = 668692522.

The previous prime is 668692499. The next prime is 668692543. The reversal of 668692523 is 325296866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 668692523 - 2⁶ = 668692459 is a prime.

It is a super-2 number, since 2×668692523² = 894299380632211058, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (668692543) 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, 334346261 + 334346262.

It is an arithmetic number, because the mean of its divisors is an integer number (334346262).

Almost surely, 2^668692523 is an apocalyptic number.

668692523 is a deficient number, since it is larger than the sum of its proper divisors (1).

668692523 is an equidigital number, since it uses as much as digits as its factorization.

668692523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 933120, while the sum is 47.

The square root of 668692523 is about 25859.0897558286. The cubic root of 668692523 is about 874.4644441909.

The spelling of 668692523 in words is "six hundred sixty-eight million, six hundred ninety-two thousand, five hundred twenty-three".