646641859 has 8 divisors (see below), whose sum is σ = 665195168. Its totient is φ = 628145280.

The previous prime is 646641851. The next prime is 646641881. The reversal of 646641859 is 958146646.

646641859 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 646641859 - 2³ = 646641851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646641851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9499 + ... + 37195.

It is an arithmetic number, because the mean of its divisors is an integer number (83149396).

Almost surely, 2^646641859 is an apocalyptic number.

646641859 is a deficient number, since it is larger than the sum of its proper divisors (18553309).

646641859 is a wasteful number, since it uses less digits than its factorization.

646641859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28365.

The product of its digits is 1244160, while the sum is 49.

The square root of 646641859 is about 25429.1537216636. The cubic root of 646641859 is about 864.7447581305.

The spelling of 646641859 in words is "six hundred forty-six million, six hundred forty-one thousand, eight hundred fifty-nine".