642065 has 4 divisors (see below), whose sum is σ = 770484. Its totient is φ = 513648.

The previous prime is 642049. The next prime is 642071. The reversal of 642065 is 560246.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 332929 + 309136 = 577^2 + 556^2 .

It is a cyclic number.

It is not a de Polignac number, because 642065 - 2⁴ = 642049 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 642065.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64202 + ... + 64211.

It is an arithmetic number, because the mean of its divisors is an integer number (192621).

2⁶⁴²⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

642065 is a deficient number, since it is larger than the sum of its proper divisors (128419).

642065 is a wasteful number, since it uses less digits than its factorization.

642065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128418.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 642065 is about 801.2895856056. The cubic root of 642065 is about 86.2699736700.

The spelling of 642065 in words is "six hundred forty-two thousand, sixty-five".