1000021843 has 2 divisors, whose sum is σ = 1000021844. Its totient is φ = 1000021842.

The previous prime is 1000021823. The next prime is 1000021849. The reversal of 1000021843 is 3481200001.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1000021843 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1000021843.

It is not a weakly prime, because it can be changed into another prime (1000021849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500010921 + 500010922.

It is an arithmetic number, because the mean of its divisors is an integer number (500010922).

Almost surely, 2^1000021843 is an apocalyptic number.

1000021843 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000021843 is an equidigital number, since it uses as much as digits as its factorization.

1000021843 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 1000021843 is about 31623.1219679525. The cubic root of 1000021843 is about 1000.0072809470.

Adding to 1000021843 its reverse (3481200001), we get a palindrome (4481221844).

The spelling of 1000021843 in words is "one billion, twenty-one thousand, eight hundred forty-three".