999921983 has 2 divisors, whose sum is σ = 999921984. Its totient is φ = 999921982.

The previous prime is 999921977. The next prime is 999922013. The reversal of 999921983 is 389129999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999921983 - 2¹⁰ = 999920959 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999921383) 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, 499960991 + 499960992.

It is an arithmetic number, because the mean of its divisors is an integer number (499960992).

Almost surely, 2^999921983 is an apocalyptic number.

999921983 is a deficient number, since it is larger than the sum of its proper divisors (1).

999921983 is an equidigital number, since it uses as much as digits as its factorization.

999921983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2834352, while the sum is 59.

The square root of 999921983 is about 31621.5430205422. The cubic root of 999921983 is about 999.9739936570.

The spelling of 999921983 in words is "nine hundred ninety-nine million, nine hundred twenty-one thousand, nine hundred eighty-three".