9991963 has 2 divisors, whose sum is σ = 9991964.
Its totient is φ = 9991962.
The previous prime is 9991939. The next prime is 9991973. The reversal of 9991963 is 3691999.
9991963 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 9991963 - 29 = 9991451 is a prime.
9991963 is a lucky number.
It is not a weakly prime, because it can be changed into another prime (9991973) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (13) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995981 + 4995982.
It is an arithmetic number, because the mean of its divisors is an integer number (4995982).
Almost surely, 29991963 is an apocalyptic number.
9991963 is a deficient number, since it is larger than the sum of its proper divisors (1).
9991963 is an equidigital number, since it uses as much as digits as its factorization.
9991963 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 118098, while the sum is 46.
The square root of 9991963 is about 3161.0066434603.
The cubic root of 9991963 is about 215.3857362285.
The spelling of 9991963 in words is "nine million, nine hundred ninety-one thousand, nine hundred sixty-three".