665505677 has 2 divisors, whose sum is σ = 665505678. Its totient is φ = 665505676.

The previous prime is 665505641. The next prime is 665505721. The reversal of 665505677 is 776505566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 592727716 + 72777961 = 24346^2 + 8531^2 .

It is a cyclic number.

It is not a de Polignac number, because 665505677 - 2²⁴ = 648728461 is a prime.

It is a super-2 number, since 2×665505677² = 885795612238456658, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665505637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332752838 + 332752839.

It is an arithmetic number, because the mean of its divisors is an integer number (332752839).

Almost surely, 2^665505677 is an apocalyptic number.

It is an amenable number.

665505677 is a deficient number, since it is larger than the sum of its proper divisors (1).

665505677 is an equidigital number, since it uses as much as digits as its factorization.

665505677 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1323000, while the sum is 47.

The square root of 665505677 is about 25797.3967097457. The cubic root of 665505677 is about 873.0730611308.

It can be divided in two parts, 66550 and 5677, that added together give a palindrome (72227).

The spelling of 665505677 in words is "six hundred sixty-five million, five hundred five thousand, six hundred seventy-seven".