642165 has 16 divisors (see below), whose sum is σ = 1061376. Its totient is φ = 331200.

The previous prime is 642163. The next prime is 642197. The reversal of 642165 is 561246.

It is not a de Polignac number, because 642165 - 2¹ = 642163 is a prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642163) 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, 226 + ... + 1155.

It is an arithmetic number, because the mean of its divisors is an integer number (66336).

2⁶⁴²¹⁶⁵ is an apocalyptic number.

It is an amenable number.

642165 is a deficient number, since it is larger than the sum of its proper divisors (419211).

642165 is a wasteful number, since it uses less digits than its factorization.

642165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1420.

The product of its digits is 1440, while the sum is 24.

The square root of 642165 is about 801.3519825894. The cubic root of 642165 is about 86.2744522143.

The spelling of 642165 in words is "six hundred forty-two thousand, one hundred sixty-five".