645937 has 2 divisors, whose sum is σ = 645938. Its totient is φ = 645936.

The previous prime is 645907. The next prime is 645941. The reversal of 645937 is 739546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 633616 + 12321 = 796^2 + 111^2 .

It is a cyclic number.

It is not a de Polignac number, because 645937 - 2¹¹ = 643889 is a prime.

It is not a weakly prime, because it can be changed into another prime (645907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322968 + 322969.

It is an arithmetic number, because the mean of its divisors is an integer number (322969).

2⁶⁴⁵⁹³⁷ is an apocalyptic number.

It is an amenable number.

645937 is a deficient number, since it is larger than the sum of its proper divisors (1).

645937 is an equidigital number, since it uses as much as digits as its factorization.

645937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 34.

The square root of 645937 is about 803.7020592234. The cubic root of 645937 is about 86.4430444668.

The spelling of 645937 in words is "six hundred forty-five thousand, nine hundred thirty-seven".