664970 has 16 divisors (see below), whose sum is σ = 1238760. Its totient is φ = 256704.

The previous prime is 664967. The next prime is 664973. The reversal of 664970 is 79466.

664970 is nontrivially palindromic in base 4.

It is an interprime number because it is at equal distance from previous prime (664967) and next prime (664973).

It can be written as a sum of positive squares in 4 ways, for example, as 477481 + 187489 = 691^2 + 433^2 .

It is a Curzon number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (664973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 857 + ... + 1436.

2⁶⁶⁴⁹⁷⁰ is an apocalyptic number.

664970 is a deficient number, since it is larger than the sum of its proper divisors (573790).

664970 is a wasteful number, since it uses less digits than its factorization.

664970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2329.

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 664970 is about 815.4569271274. The cubic root of 664970 is about 87.2838747729.

The spelling of 664970 in words is "six hundred sixty-four thousand, nine hundred seventy".