664646456 has 16 divisors (see below), whose sum is σ = 1300395600. Its totient is φ = 317874304.

The previous prime is 664646453. The next prime is 664646459. The reversal of 664646456 is 654646466.

It is an interprime number because it is at equal distance from previous prime (664646453) and next prime (664646459).

It is a super-2 number, since 2×664646456² = 883509822946719872, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 664646456.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664646453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1805921 + ... + 1806288.

It is an arithmetic number, because the mean of its divisors is an integer number (81274725).

Almost surely, 2^664646456 is an apocalyptic number.

It is an amenable number.

664646456 is a deficient number, since it is larger than the sum of its proper divisors (635749144).

664646456 is a wasteful number, since it uses less digits than its factorization.

664646456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3612238 (or 3612234 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 47.

The square root of 664646456 is about 25780.7380809782. The cubic root of 664646456 is about 872.6971636209.

The spelling of 664646456 in words is "six hundred sixty-four million, six hundred forty-six thousand, four hundred fifty-six".