646061 has 4 divisors (see below), whose sum is σ = 695772. Its totient is φ = 596352.

The previous prime is 646039. The next prime is 646067. The reversal of 646061 is 160646.

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 36100 + 609961 = 190^2 + 781^2 .

It is a cyclic number.

It is not a de Polignac number, because 646061 - 2¹⁰ = 645037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646067) 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 3 ways as a sum of consecutive naturals, for example, 24836 + ... + 24861.

It is an arithmetic number, because the mean of its divisors is an integer number (173943).

2⁶⁴⁶⁰⁶¹ is an apocalyptic number.

It is an amenable number.

646061 is a deficient number, since it is larger than the sum of its proper divisors (49711).

646061 is a wasteful number, since it uses less digits than its factorization.

646061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49710.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 646061 is about 803.7791985365. The cubic root of 646061 is about 86.4485755798.

The spelling of 646061 in words is "six hundred forty-six thousand, sixty-one".