664064 has 20 divisors (see below), whose sum is σ = 1327854. Its totient is φ = 331776.

The previous prime is 664061. The next prime is 664067. The reversal of 664064 is 460466.

It is an interprime number because it is at equal distance from previous prime (664061) and next prime (664067).

It can be written as a sum of positive squares in only one way, i.e., 350464 + 313600 = 592^2 + 560^2 .

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 137 + ... + 1160.

2⁶⁶⁴⁰⁶⁴ is an apocalyptic number.

664064 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

664064 is a deficient number, since it is larger than the sum of its proper divisors (663790).

664064 is an equidigital number, since it uses as much as digits as its factorization.

664064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1315 (or 1299 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 664064 is about 814.9012210078. The cubic root of 664064 is about 87.2442162760.

The spelling of 664064 in words is "six hundred sixty-four thousand, sixty-four".