664166564 has 12 divisors (see below), whose sum is σ = 1162694988. Its totient is φ = 331968000.

The previous prime is 664166521. The next prime is 664166567. The reversal of 664166564 is 465661466.

It can be written as a sum of positive squares in 2 ways, for example, as 346257664 + 317908900 = 18608^2 + 17830^2 .

It is a super-2 number, since 2×664166564² = 882234449471132192, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664166567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15137 + ... + 39464.

It is an arithmetic number, because the mean of its divisors is an integer number (96891249).

Almost surely, 2^664166564 is an apocalyptic number.

It is an amenable number.

664166564 is a deficient number, since it is larger than the sum of its proper divisors (498528424).

664166564 is a wasteful number, since it uses less digits than its factorization.

664166564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57646 (or 57644 counting only the distinct ones).

The product of its digits is 622080, while the sum is 44.

The square root of 664166564 is about 25771.4292191954. The cubic root of 664166564 is about 872.4870763788.

The spelling of 664166564 in words is "six hundred sixty-four million, one hundred sixty-six thousand, five hundred sixty-four".