646121 has 8 divisors (see below), whose sum is σ = 743424. Its totient is φ = 550080.

The previous prime is 646103. The next prime is 646147. The reversal of 646121 is 121646.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 646121 - 2¹⁰ = 645097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 646093 and 646102.

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 646121.

It is not an unprimeable number, because it can be changed into a prime (646181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1496 + ... + 1878.

It is an arithmetic number, because the mean of its divisors is an integer number (92928).

2⁶⁴⁶¹²¹ is an apocalyptic number.

It is an amenable number.

646121 is a deficient number, since it is larger than the sum of its proper divisors (97303).

646121 is a wasteful number, since it uses less digits than its factorization.

646121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631.

The product of its digits is 288, while the sum is 20.

The square root of 646121 is about 803.8165213530. The cubic root of 646121 is about 86.4512516707.

Adding to 646121 its reverse (121646), we get a palindrome (767767).

It can be divided in two parts, 646 and 121, that added together give a palindrome (767).

The spelling of 646121 in words is "six hundred forty-six thousand, one hundred twenty-one".