663666677 has 2 divisors, whose sum is σ = 663666678. Its totient is φ = 663666676.

The previous prime is 663666659. The next prime is 663666701. The reversal of 663666677 is 776666366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 663268516 + 398161 = 25754^2 + 631^2 .

It is a cyclic number.

It is not a de Polignac number, because 663666677 - 2¹² = 663662581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663665677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331833338 + 331833339.

It is an arithmetic number, because the mean of its divisors is an integer number (331833339).

Almost surely, 2^663666677 is an apocalyptic number.

It is an amenable number.

663666677 is a deficient number, since it is larger than the sum of its proper divisors (1).

663666677 is an equidigital number, since it uses as much as digits as its factorization.

663666677 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6858432, while the sum is 53.

The square root of 663666677 is about 25761.7289210177. The cubic root of 663666677 is about 872.2681280816.

The spelling of 663666677 in words is "six hundred sixty-three million, six hundred sixty-six thousand, six hundred seventy-seven".