645682 has 8 divisors (see below), whose sum is σ = 977436. Its totient is φ = 319872.

The previous prime is 645661. The next prime is 645683. The reversal of 645682 is 286546.

645682 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 609961 + 35721 = 781^2 + 189^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (645683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1203 + ... + 1654.

2⁶⁴⁵⁶⁸² is an apocalyptic number.

645682 is a deficient number, since it is larger than the sum of its proper divisors (331754).

645682 is a wasteful number, since it uses less digits than its factorization.

645682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2972.

The product of its digits is 11520, while the sum is 31.

The square root of 645682 is about 803.5434026859. The cubic root of 645682 is about 86.4316677754.

The spelling of 645682 in words is "six hundred forty-five thousand, six hundred eighty-two".