643170650 has 12 divisors (see below), whose sum is σ = 1196297502. Its totient is φ = 257268240.

The previous prime is 643170557. The next prime is 643170659. The reversal of 643170650 is 56071346.

It can be written as a sum of positive squares in 3 ways, for example, as 542750209 + 100420441 = 23297^2 + 10021^2 .

It is not an unprimeable number, because it can be changed into a prime (643170659) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6431657 + ... + 6431756.

Almost surely, 2^643170650 is an apocalyptic number.

643170650 is a deficient number, since it is larger than the sum of its proper divisors (553126852).

643170650 is a wasteful number, since it uses less digits than its factorization.

643170650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12863425 (or 12863420 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 643170650 is about 25360.8093325115. The cubic root of 643170650 is about 863.1946486764.

The spelling of 643170650 in words is "six hundred forty-three million, one hundred seventy thousand, six hundred fifty".