664646466 has 96 divisors (see below), whose sum is σ = 1521051840. Its totient is φ = 193311360.

The previous prime is 664646459. The next prime is 664646519.

664646466 is nontrivially palindromic in base 10.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2927845 + ... + 2928071.

It is an arithmetic number, because the mean of its divisors is an integer number (15844290).

Almost surely, 2^664646466 is an apocalyptic number.

664646466 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 664646466, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (760525920).

664646466 is an abundant number, since it is smaller than the sum of its proper divisors (856405374).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664646466 is a wasteful number, since it uses less digits than its factorization.

664646466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400 (or 389 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 48.

The square root of 664646466 is about 25780.7382749215. The cubic root of 664646466 is about 872.6971679976.

The spelling of 664646466 in words is "six hundred sixty-four million, six hundred forty-six thousand, four hundred sixty-six".