663260621 has 2 divisors, whose sum is σ = 663260622. Its totient is φ = 663260620.

The previous prime is 663260597. The next prime is 663260639. The reversal of 663260621 is 126062366.

663260621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 661261225 + 1999396 = 25715^2 + 1414^2 .

It is a cyclic number.

It is not a de Polignac number, because 663260621 - 2¹⁴ = 663244237 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663260641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331630310 + 331630311.

It is an arithmetic number, because the mean of its divisors is an integer number (331630311).

Almost surely, 2^663260621 is an apocalyptic number.

It is an amenable number.

663260621 is a deficient number, since it is larger than the sum of its proper divisors (1).

663260621 is an equidigital number, since it uses as much as digits as its factorization.

663260621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 663260621 is about 25753.8467223830. The cubic root of 663260621 is about 872.0901964083.

The spelling of 663260621 in words is "six hundred sixty-three million, two hundred sixty thousand, six hundred twenty-one".