990655999 has 2 divisors, whose sum is σ = 990656000. Its totient is φ = 990655998.

The previous prime is 990655997. The next prime is 990656003. The reversal of 990655999 is 999556099.

It is a weak prime.

It is an emirp because it is prime and its reverse (999556099) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 990655999 - 2¹ = 990655997 is a prime.

Together with 990655997, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (990655997) 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, 495327999 + 495328000.

It is an arithmetic number, because the mean of its divisors is an integer number (495328000).

Almost surely, 2^990655999 is an apocalyptic number.

990655999 is a deficient number, since it is larger than the sum of its proper divisors (1).

990655999 is an equidigital number, since it uses as much as digits as its factorization.

990655999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8857350, while the sum is 61.

The square root of 990655999 is about 31474.6882272089. The cubic root of 990655999 is about 996.8755811739.

The spelling of 990655999 in words is "nine hundred ninety million, six hundred fifty-five thousand, nine hundred ninety-nine".