9909791 has 2 divisors, whose sum is σ = 9909792. Its totient is φ = 9909790.

The previous prime is 9909787. The next prime is 9909797. The reversal of 9909791 is 1979099.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9909791 - 2² = 9909787 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9909797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4954895 + 4954896.

It is an arithmetic number, because the mean of its divisors is an integer number (4954896).

Almost surely, 2^9909791 is an apocalyptic number.

9909791 is a deficient number, since it is larger than the sum of its proper divisors (1).

9909791 is an equidigital number, since it uses as much as digits as its factorization.

9909791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 9909791 is about 3147.9820520454. The cubic root of 9909791 is about 214.7936798444.

The spelling of 9909791 in words is "nine million, nine hundred nine thousand, seven hundred ninety-one".