9991667893 has 2 divisors, whose sum is σ = 9991667894. Its totient is φ = 9991667892.

The previous prime is 9991667891. The next prime is 9991667909. The reversal of 9991667893 is 3987661999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7646977809 + 2344690084 = 87447^2 + 48422^2 .

It is a cyclic number.

It is not a de Polignac number, because 9991667893 - 2¹ = 9991667891 is a prime.

Together with 9991667891, 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 (9991667891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995833946 + 4995833947.

It is an arithmetic number, because the mean of its divisors is an integer number (4995833947).

Almost surely, 2^9991667893 is an apocalyptic number.

It is an amenable number.

9991667893 is a deficient number, since it is larger than the sum of its proper divisors (1).

9991667893 is an equidigital number, since it uses as much as digits as its factorization.

9991667893 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 39680928, while the sum is 67.

The square root of 9991667893 is about 99958.3307833819. The cubic root of 9991667893 is about 2153.8361577545.

The spelling of 9991667893 in words is "nine billion, nine hundred ninety-one million, six hundred sixty-seven thousand, eight hundred ninety-three".