664694487 has 12 divisors (see below), whose sum is σ = 961416144. Its totient is φ = 442528800.

The previous prime is 664694479. The next prime is 664694519. The reversal of 664694487 is 784496466.

664694487 is a `hidden beast` number, since 66 + 469 + 44 + 87 = 666.

It is not a de Polignac number, because 664694487 - 2³ = 664694479 is a prime.

It is a super-2 number, since 2×664694487² = 883637522096386338, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664694417) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43014 + ... + 56387.

It is an arithmetic number, because the mean of its divisors is an integer number (80118012).

Almost surely, 2^664694487 is an apocalyptic number.

664694487 is a deficient number, since it is larger than the sum of its proper divisors (296721657).

664694487 is a wasteful number, since it uses less digits than its factorization.

664694487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100150 (or 100147 counting only the distinct ones).

The product of its digits is 6967296, while the sum is 54.

The square root of 664694487 is about 25781.6695929492. The cubic root of 664694487 is about 872.7181850764.

The spelling of 664694487 in words is "six hundred sixty-four million, six hundred ninety-four thousand, four hundred eighty-seven".