650021 has 4 divisors (see below), whose sum is σ = 652044. Its totient is φ = 648000.

The previous prime is 650017. The next prime is 650059. The reversal of 650021 is 120056.

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 592900 + 57121 = 770^2 + 239^2 .

It is a cyclic number.

It is not a de Polignac number, because 650021 - 2² = 650017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 649978 and 650005.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 650021.

It is not an unprimeable number, because it can be changed into a prime (650011) 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 3 ways as a sum of consecutive naturals, for example, 410 + ... + 1211.

It is an arithmetic number, because the mean of its divisors is an integer number (163011).

2⁶⁵⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

650021 is a deficient number, since it is larger than the sum of its proper divisors (2023).

650021 is a wasteful number, since it uses less digits than its factorization.

650021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 650021 is about 806.2387983718. The cubic root of 650021 is about 86.6248433969.

Adding to 650021 its reverse (120056), we get a palindrome (770077).

The spelling of 650021 in words is "six hundred fifty thousand, twenty-one".