645129 has 12 divisors (see below), whose sum is σ = 954096. Its totient is φ = 419832.

The previous prime is 645097. The next prime is 645131. The reversal of 645129 is 921546.

645129 is a `hidden beast` number, since 645 + 12 + 9 = 666.

It is not a de Polignac number, because 645129 - 2⁵ = 645097 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (645149) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 447 + ... + 1220.

It is an arithmetic number, because the mean of its divisors is an integer number (79508).

2⁶⁴⁵¹²⁹ is an apocalyptic number.

It is an amenable number.

645129 is a deficient number, since it is larger than the sum of its proper divisors (308967).

645129 is a wasteful number, since it uses less digits than its factorization.

645129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1716 (or 1713 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 645129 is about 803.1992280873. The cubic root of 645129 is about 86.4069856749.

The spelling of 645129 in words is "six hundred forty-five thousand, one hundred twenty-nine".