665453869 has 2 divisors, whose sum is σ = 665453870. Its totient is φ = 665453868.

The previous prime is 665453863. The next prime is 665453947. The reversal of 665453869 is 968354566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 594725769 + 70728100 = 24387^2 + 8410^2 .

It is a cyclic number.

It is not a de Polignac number, because 665453869 - 2⁵ = 665453837 is a prime.

It is a super-2 number, since 2×665453869² = 885657703534138322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665453863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332726934 + 332726935.

It is an arithmetic number, because the mean of its divisors is an integer number (332726935).

Almost surely, 2^665453869 is an apocalyptic number.

It is an amenable number.

665453869 is a deficient number, since it is larger than the sum of its proper divisors (1).

665453869 is an equidigital number, since it uses as much as digits as its factorization.

665453869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4665600, while the sum is 52.

The square root of 665453869 is about 25796.3925578752. The cubic root of 665453869 is about 873.0504050040.

The spelling of 665453869 in words is "six hundred sixty-five million, four hundred fifty-three thousand, eight hundred sixty-nine".