664961177 has 2 divisors, whose sum is σ = 664961178. Its totient is φ = 664961176.

The previous prime is 664961173. The next prime is 664961179. The reversal of 664961177 is 771169466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 464143936 + 200817241 = 21544^2 + 14171^2 .

It is a cyclic number.

It is not a de Polignac number, because 664961177 - 2² = 664961173 is a prime.

Together with 664961179, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (664961173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332480588 + 332480589.

It is an arithmetic number, because the mean of its divisors is an integer number (332480589).

Almost surely, 2^664961177 is an apocalyptic number.

It is an amenable number.

664961177 is a deficient number, since it is larger than the sum of its proper divisors (1).

664961177 is an equidigital number, since it uses as much as digits as its factorization.

664961177 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 47.

The square root of 664961177 is about 25786.8411597854. The cubic root of 664961177 is about 872.8348873593.

The spelling of 664961177 in words is "six hundred sixty-four million, nine hundred sixty-one thousand, one hundred seventy-seven".