664395061 has 4 divisors (see below), whose sum is σ = 724794624. Its totient is φ = 603995500.

The previous prime is 664395041. The next prime is 664395077. The reversal of 664395061 is 160593466.

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.

It is a cyclic number.

It is not a de Polignac number, because 664395061 - 2⁷ = 664394933 is a prime.

It is a super-3 number, since 3×664395061³ (a number of 27 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664395031) 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, 30199765 + ... + 30199786.

It is an arithmetic number, because the mean of its divisors is an integer number (181198656).

Almost surely, 2^664395061 is an apocalyptic number.

It is an amenable number.

664395061 is a deficient number, since it is larger than the sum of its proper divisors (60399563).

664395061 is a wasteful number, since it uses less digits than its factorization.

664395061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60399562.

The product of its (nonzero) digits is 116640, while the sum is 40.

The square root of 664395061 is about 25775.8619836466. The cubic root of 664395061 is about 872.5871204703.

The spelling of 664395061 in words is "six hundred sixty-four million, three hundred ninety-five thousand, sixty-one".