999856049 has 2 divisors, whose sum is σ = 999856050. Its totient is φ = 999856048.

The previous prime is 999856031. The next prime is 999856061. The reversal of 999856049 is 940658999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 982383649 + 17472400 = 31343^2 + 4180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999856049 is a prime.

It is not a weakly prime, because it can be changed into another prime (999856549) 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, 499928024 + 499928025.

It is an arithmetic number, because the mean of its divisors is an integer number (499928025).

Almost surely, 2^999856049 is an apocalyptic number.

It is an amenable number.

999856049 is a deficient number, since it is larger than the sum of its proper divisors (1).

999856049 is an equidigital number, since it uses as much as digits as its factorization.

999856049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6298560, while the sum is 59.

The square root of 999856049 is about 31620.5004546101. The cubic root of 999856049 is about 999.9520140307.

The spelling of 999856049 in words is "nine hundred ninety-nine million, eight hundred fifty-six thousand, forty-nine".