668696953 has 2 divisors, whose sum is σ = 668696954. Its totient is φ = 668696952.

The previous prime is 668696929. The next prime is 668696971. The reversal of 668696953 is 359696866.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 525463929 + 143233024 = 22923^2 + 11968^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668696953 is a prime.

It is a super-2 number, since 2×668696953² = 894311229902968418, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (668696983) 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, 334348476 + 334348477.

It is an arithmetic number, because the mean of its divisors is an integer number (334348477).

Almost surely, 2^668696953 is an apocalyptic number.

It is an amenable number.

668696953 is a deficient number, since it is larger than the sum of its proper divisors (1).

668696953 is an equidigital number, since it uses as much as digits as its factorization.

668696953 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12597120, while the sum is 58.

The square root of 668696953 is about 25859.1754122207. The cubic root of 668696953 is about 874.4663752573.

The spelling of 668696953 in words is "six hundred sixty-eight million, six hundred ninety-six thousand, nine hundred fifty-three".