664647041 has 2 divisors, whose sum is σ = 664647042. Its totient is φ = 664647040.

The previous prime is 664647013. The next prime is 664647047. The reversal of 664647041 is 140746466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 527850625 + 136796416 = 22975^2 + 11696^2 .

It is a cyclic number.

It is not a de Polignac number, because 664647041 - 2²⁶ = 597538177 is a prime.

It is a super-4 number, since 4×664647041⁴ (a number of 36 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 664646986 and 664647004.

It is not a weakly prime, because it can be changed into another prime (664647047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332323520 + 332323521.

It is an arithmetic number, because the mean of its divisors is an integer number (332323521).

Almost surely, 2^664647041 is an apocalyptic number.

It is an amenable number.

664647041 is a deficient number, since it is larger than the sum of its proper divisors (1).

664647041 is an equidigital number, since it uses as much as digits as its factorization.

664647041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 38.

The square root of 664647041 is about 25780.7494266555. The cubic root of 664647041 is about 872.6974196606.

The spelling of 664647041 in words is "six hundred sixty-four million, six hundred forty-seven thousand, forty-one".