646644311 has 4 divisors (see below), whose sum is σ = 646720800. Its totient is φ = 646567824.

The previous prime is 646644253. The next prime is 646644337. The reversal of 646644311 is 113446646.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 113446646 = 2 ⋅56723323.

It is a cyclic number.

It is not a de Polignac number, because 646644311 - 2¹⁸ = 646382167 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 (646644391) 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, 23726 + ... + 43083.

It is an arithmetic number, because the mean of its divisors is an integer number (161680200).

Almost surely, 2^646644311 is an apocalyptic number.

646644311 is a deficient number, since it is larger than the sum of its proper divisors (76489).

646644311 is an equidigital number, since it uses as much as digits as its factorization.

646644311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76488.

The product of its digits is 41472, while the sum is 35.

The square root of 646644311 is about 25429.2019339971. The cubic root of 646644311 is about 864.7458511371.

The spelling of 646644311 in words is "six hundred forty-six million, six hundred forty-four thousand, three hundred eleven".