645850 has 12 divisors (see below), whose sum is σ = 1201374. Its totient is φ = 258320.

The previous prime is 645839. The next prime is 645851. The reversal of 645850 is 58546.

It can be written as a sum of positive squares in 3 ways, for example, as 491401 + 154449 = 701^2 + 393^2 .

It is not an unprimeable number, because it can be changed into a prime (645851) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6409 + ... + 6508.

2⁶⁴⁵⁸⁵⁰ is an apocalyptic number.

645850 is a deficient number, since it is larger than the sum of its proper divisors (555524).

645850 is a wasteful number, since it uses less digits than its factorization.

645850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12929 (or 12924 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 645850 is about 803.6479328661. The cubic root of 645850 is about 86.4391633439.

The spelling of 645850 in words is "six hundred forty-five thousand, eight hundred fifty".