664541773 has 6 divisors (see below), whose sum is σ = 773038446. Its totient is φ = 569607192.

The previous prime is 664541767. The next prime is 664541803. The reversal of 664541773 is 377145466.

664541773 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 610930089 + 53611684 = 24717^2 + 7322^2 .

It is not a de Polignac number, because 664541773 - 2⁹ = 664541261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664541743) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6780990 + ... + 6781087.

It is an arithmetic number, because the mean of its divisors is an integer number (128839741).

Almost surely, 2^664541773 is an apocalyptic number.

It is an amenable number.

664541773 is a deficient number, since it is larger than the sum of its proper divisors (108496673).

664541773 is a wasteful number, since it uses less digits than its factorization.

664541773 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13562091 (or 13562084 counting only the distinct ones).

The product of its digits is 423360, while the sum is 43.

The square root of 664541773 is about 25778.7077449588. The cubic root of 664541773 is about 872.6513440963.

The spelling of 664541773 in words is "six hundred sixty-four million, five hundred forty-one thousand, seven hundred seventy-three".