1000643863 has 2 divisors, whose sum is σ = 1000643864. Its totient is φ = 1000643862.

The previous prime is 1000643857. The next prime is 1000643881. The reversal of 1000643863 is 3683460001.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1000643863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1000643803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500321931 + 500321932.

It is an arithmetic number, because the mean of its divisors is an integer number (500321932).

Almost surely, 2^1000643863 is an apocalyptic number.

1000643863 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000643863 is an equidigital number, since it uses as much as digits as its factorization.

1000643863 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 1000643863 is about 31632.9553314261. The cubic root of 1000643863 is about 1000.2145749543.

The spelling of 1000643863 in words is "one billion, six hundred forty-three thousand, eight hundred sixty-three".