999996649 has 2 divisors, whose sum is σ = 999996650. Its totient is φ = 999996648.

The previous prime is 999996643. The next prime is 999996671. The reversal of 999996649 is 946699999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 809004249 + 190992400 = 28443^2 + 13820^2 .

It is a cyclic number.

It is not a de Polignac number, because 999996649 - 2²³ = 991608041 is a prime.

It is a super-2 number, since 2×999996649² = 1999986596022458402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (999996643) 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, 499998324 + 499998325.

It is an arithmetic number, because the mean of its divisors is an integer number (499998325).

Almost surely, 2^999996649 is an apocalyptic number.

It is an amenable number.

999996649 is a deficient number, since it is larger than the sum of its proper divisors (1).

999996649 is an equidigital number, since it uses as much as digits as its factorization.

999996649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 76527504, while the sum is 70.

The square root of 999996649 is about 31622.7236176772. The cubic root of 999996649 is about 999.9988829988.

The spelling of 999996649 in words is "nine hundred ninety-nine million, nine hundred ninety-six thousand, six hundred forty-nine".