665647369 has 2 divisors, whose sum is σ = 665647370. Its totient is φ = 665647368.

The previous prime is 665647363. The next prime is 665647373. The reversal of 665647369 is 963746566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 640697344 + 24950025 = 25312^2 + 4995^2 .

It is a cyclic number.

It is not a de Polignac number, because 665647369 - 2⁵ = 665647337 is a prime.

It is a super-2 number, since 2×665647369² = 886172839713244322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (665647363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332823684 + 332823685.

It is an arithmetic number, because the mean of its divisors is an integer number (332823685).

Almost surely, 2^665647369 is an apocalyptic number.

It is an amenable number.

665647369 is a deficient number, since it is larger than the sum of its proper divisors (1).

665647369 is an equidigital number, since it uses as much as digits as its factorization.

665647369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 52.

The square root of 665647369 is about 25800.1428096823. The cubic root of 665647369 is about 873.1350183732.

The spelling of 665647369 in words is "six hundred sixty-five million, six hundred forty-seven thousand, three hundred sixty-nine".