646556366 has 4 divisors (see below), whose sum is σ = 969834552. Its totient is φ = 323278182.

The previous prime is 646556357. The next prime is 646556387. The reversal of 646556366 is 663655646.

646556366 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 646556366.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161639090 + ... + 161639093.

It is an arithmetic number, because the mean of its divisors is an integer number (242458638).

Almost surely, 2^646556366 is an apocalyptic number.

646556366 is a deficient number, since it is larger than the sum of its proper divisors (323278186).

646556366 is a wasteful number, since it uses less digits than its factorization.

646556366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323278185.

The product of its digits is 2332800, while the sum is 47.

The square root of 646556366 is about 25427.4726624570. The cubic root of 646556366 is about 864.7066469355.

The spelling of 646556366 in words is "six hundred forty-six million, five hundred fifty-six thousand, three hundred sixty-six".