643876250 has 40 divisors (see below), whose sum is σ = 1210562496. Its totient is φ = 256766000.

The previous prime is 643876249. The next prime is 643876267. The reversal of 643876250 is 52678346.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 643876198 and 643876207.

It is an unprimeable number.

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 in 19 ways as a sum of consecutive naturals, for example, 583199 + ... + 584301.

Almost surely, 2^643876250 is an apocalyptic number.

643876250 is a deficient number, since it is larger than the sum of its proper divisors (566686246).

643876250 is a wasteful number, since it uses less digits than its factorization.

643876250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1592 (or 1577 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 41.

The square root of 643876250 is about 25374.7167471875. The cubic root of 643876250 is about 863.5101935218.

The spelling of 643876250 in words is "six hundred forty-three million, eight hundred seventy-six thousand, two hundred fifty".