664442073 has 24 divisors (see below), whose sum is σ = 984686976. Its totient is φ = 431589600.

The previous prime is 664442071. The next prime is 664442081. The reversal of 664442073 is 370244466.

664442073 is a `hidden beast` number, since 6 + 6 + 444 + 207 + 3 = 666.

It is not a de Polignac number, because 664442073 - 2¹ = 664442071 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (664442071) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53088 + ... + 64398.

It is an arithmetic number, because the mean of its divisors is an integer number (41028624).

Almost surely, 2^664442073 is an apocalyptic number.

It is an amenable number.

664442073 is a deficient number, since it is larger than the sum of its proper divisors (320244903).

664442073 is a wasteful number, since it uses less digits than its factorization.

664442073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11485 (or 11482 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 36.

The square root of 664442073 is about 25776.7739059798. The cubic root of 664442073 is about 872.6077011462.

The spelling of 664442073 in words is "six hundred sixty-four million, four hundred forty-two thousand, seventy-three".