643566283 has 2 divisors, whose sum is σ = 643566284. Its totient is φ = 643566282.

The previous prime is 643566221. The next prime is 643566349. The reversal of 643566283 is 382665346.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643566283 is a prime.

It is a super-2 number, since 2×643566283² = 828355121228872178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (643566683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321783141 + 321783142.

It is an arithmetic number, because the mean of its divisors is an integer number (321783142).

Almost surely, 2^643566283 is an apocalyptic number.

643566283 is a deficient number, since it is larger than the sum of its proper divisors (1).

643566283 is an equidigital number, since it uses as much as digits as its factorization.

643566283 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 43.

The square root of 643566283 is about 25368.6082196087. The cubic root of 643566283 is about 863.3716044545.

The spelling of 643566283 in words is "six hundred forty-three million, five hundred sixty-six thousand, two hundred eighty-three".