663065261 has 4 divisors (see below), whose sum is σ = 663116832. Its totient is φ = 663013692.

The previous prime is 663065209. The next prime is 663065267. The reversal of 663065261 is 162560366.

663065261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 663065261 - 2¹⁴ = 663048877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663065267) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10880 + ... + 38006.

It is an arithmetic number, because the mean of its divisors is an integer number (165779208).

Almost surely, 2^663065261 is an apocalyptic number.

It is an amenable number.

663065261 is a deficient number, since it is larger than the sum of its proper divisors (51571).

663065261 is a wasteful number, since it uses less digits than its factorization.

663065261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51570.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 663065261 is about 25750.0536115947. The cubic root of 663065261 is about 872.0045647749.

The spelling of 663065261 in words is "six hundred sixty-three million, sixty-five thousand, two hundred sixty-one".