999201001 has 2 divisors, whose sum is σ = 999201002. Its totient is φ = 999201000.

The previous prime is 999200999. The next prime is 999201023. The reversal of 999201001 is 100102999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 930311001 + 68890000 = 30501^2 + 8300^2 .

It is a cyclic number.

It is not a de Polignac number, because 999201001 - 2¹ = 999200999 is a prime.

Together with 999200999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (999201041) 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, 499600500 + 499600501.

It is an arithmetic number, because the mean of its divisors is an integer number (499600501).

Almost surely, 2^999201001 is an apocalyptic number.

It is an amenable number.

999201001 is a deficient number, since it is larger than the sum of its proper divisors (1).

999201001 is an equidigital number, since it uses as much as digits as its factorization.

999201001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1458, while the sum is 31.

The square root of 999201001 is about 31610.1407937390. The cubic root of 999201001 is about 999.7335960352.

The spelling of 999201001 in words is "nine hundred ninety-nine million, two hundred one thousand, one".