645827 has 16 divisors (see below), whose sum is σ = 817152. Its totient is φ = 496800.

The previous prime is 645803. The next prime is 645833. The reversal of 645827 is 728546.

It is a cyclic number.

It is not a de Polignac number, because 645827 - 2⁶ = 645763 is a prime.

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 645793 and 645802.

It is not an unprimeable number, because it can be changed into a prime (645857) 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 in 15 ways as a sum of consecutive naturals, for example, 4202 + ... + 4352.

It is an arithmetic number, because the mean of its divisors is an integer number (51072).

2⁶⁴⁵⁸²⁷ is an apocalyptic number.

645827 is a deficient number, since it is larger than the sum of its proper divisors (171325).

645827 is a wasteful number, since it uses less digits than its factorization.

645827 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218.

The product of its digits is 13440, while the sum is 32.

The square root of 645827 is about 803.6336229900. The cubic root of 645827 is about 86.4381372417.

The spelling of 645827 in words is "six hundred forty-five thousand, eight hundred twenty-seven".