646444306 has 4 divisors (see below), whose sum is σ = 969666462. Its totient is φ = 323222152.

The previous prime is 646444301. The next prime is 646444313. The reversal of 646444306 is 603444646.

646444306 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 can be written as a sum of positive squares in only one way, i.e., 608066281 + 38378025 = 24659^2 + 6195^2 .

It is not an unprimeable number, because it can be changed into a prime (646444301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161611075 + ... + 161611078.

Almost surely, 2^646444306 is an apocalyptic number.

646444306 is a deficient number, since it is larger than the sum of its proper divisors (323222156).

646444306 is a wasteful number, since it uses less digits than its factorization.

646444306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323222155.

The product of its (nonzero) digits is 165888, while the sum is 37.

The square root of 646444306 is about 25425.2690447909. The cubic root of 646444306 is about 864.6566875761.

The spelling of 646444306 in words is "six hundred forty-six million, four hundred forty-four thousand, three hundred six".