643863466 has 4 divisors (see below), whose sum is σ = 965795202. Its totient is φ = 321931732.

The previous prime is 643863463. The next prime is 643863511. The reversal of 643863466 is 664368346.

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., 495730225 + 148133241 = 22265^2 + 12171^2 .

It is not an unprimeable number, because it can be changed into a prime (643863463) 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 as a sum of consecutive naturals, namely, 160965865 + ... + 160965868.

Almost surely, 2^643863466 is an apocalyptic number.

643863466 is a deficient number, since it is larger than the sum of its proper divisors (321931736).

643863466 is a wasteful number, since it uses less digits than its factorization.

643863466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321931735.

The product of its digits is 1492992, while the sum is 46.

The square root of 643863466 is about 25374.4648416474. The cubic root of 643863466 is about 863.5044785585.

The spelling of 643863466 in words is "six hundred forty-three million, eight hundred sixty-three thousand, four hundred sixty-six".