664537 has 2 divisors, whose sum is σ = 664538. Its totient is φ = 664536.

The previous prime is 664529. The next prime is 664549. The reversal of 664537 is 735466.

664537 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 495616 + 168921 = 704^2 + 411^2 .

It is a cyclic number.

It is not a de Polignac number, because 664537 - 2³ = 664529 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 664499 and 664508.

It is not a weakly prime, because it can be changed into another prime (664507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332268 + 332269.

It is an arithmetic number, because the mean of its divisors is an integer number (332269).

2⁶⁶⁴⁵³⁷ is an apocalyptic number.

It is an amenable number.

664537 is a deficient number, since it is larger than the sum of its proper divisors (1).

664537 is an equidigital number, since it uses as much as digits as its factorization.

664537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 31.

The square root of 664537 is about 815.1913885708. The cubic root of 664537 is about 87.2649254850.

The spelling of 664537 in words is "six hundred sixty-four thousand, five hundred thirty-seven".