664494444 has 36 divisors (see below), whose sum is σ = 1680568344. Its totient is φ = 221382912.

The previous prime is 664494427. The next prime is 664494451. The reversal of 664494444 is 444494466.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×664494444² = 883105732213738272, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 664494444.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 92179 + ... + 99125.

It is an arithmetic number, because the mean of its divisors is an integer number (46682454).

Almost surely, 2^664494444 is an apocalyptic number.

It is an amenable number.

664494444 is an abundant number, since it is smaller than the sum of its proper divisors (1016073900).

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

664494444 is a wasteful number, since it uses less digits than its factorization.

664494444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9614 (or 9609 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 45.

The square root of 664494444 is about 25777.7897423344. The cubic root of 664494444 is about 872.6306267149.

The spelling of 664494444 in words is "six hundred sixty-four million, four hundred ninety-four thousand, four hundred forty-four".