9923891 has 2 divisors, whose sum is σ = 9923892. Its totient is φ = 9923890.

The previous prime is 9923861. The next prime is 9923897. The reversal of 9923891 is 1983299.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9923891 is a prime.

It is a super-2 number, since 2×9923891² = 196967225159762, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9923897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4961945 + 4961946.

It is an arithmetic number, because the mean of its divisors is an integer number (4961946).

Almost surely, 2^9923891 is an apocalyptic number.

9923891 is a deficient number, since it is larger than the sum of its proper divisors (1).

9923891 is an equidigital number, since it uses as much as digits as its factorization.

9923891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34992, while the sum is 41.

The square root of 9923891 is about 3150.2207859133. The cubic root of 9923891 is about 214.8955035735.

The spelling of 9923891 in words is "nine million, nine hundred twenty-three thousand, eight hundred ninety-one".