665264617 has 2 divisors, whose sum is σ = 665264618. Its totient is φ = 665264616.

The previous prime is 665264599. The next prime is 665264683. The reversal of 665264617 is 716462566.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 600446016 + 64818601 = 24504^2 + 8051^2 .

It is a cyclic number.

It is not a de Polignac number, because 665264617 - 2²³ = 656876009 is a prime.

It is not a weakly prime, because it can be changed into another prime (665264687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332632308 + 332632309.

It is an arithmetic number, because the mean of its divisors is an integer number (332632309).

Almost surely, 2^665264617 is an apocalyptic number.

It is an amenable number.

665264617 is a deficient number, since it is larger than the sum of its proper divisors (1).

665264617 is an equidigital number, since it uses as much as digits as its factorization.

665264617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 43.

The square root of 665264617 is about 25792.7241097175. The cubic root of 665264617 is about 872.9676333256.

The spelling of 665264617 in words is "six hundred sixty-five million, two hundred sixty-four thousand, six hundred seventeen".