9958891 has 4 divisors (see below), whose sum is σ = 10000800. Its totient is φ = 9916984.

The previous prime is 9958873. The next prime is 9958901. The reversal of 9958891 is 1988599.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9958891 - 2⁷ = 9958763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9958841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20596 + ... + 21073.

It is an arithmetic number, because the mean of its divisors is an integer number (2500200).

Almost surely, 2^9958891 is an apocalyptic number.

9958891 is a deficient number, since it is larger than the sum of its proper divisors (41909).

9958891 is a wasteful number, since it uses less digits than its factorization.

9958891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41908.

The product of its digits is 233280, while the sum is 49.

The square root of 9958891 is about 3155.7710626723. The cubic root of 9958891 is about 215.1478413482.

It can be divided in two parts, 9958 and 891, that multiplied together give a triangular number (8872578 = T₄₂₁₂).

The spelling of 9958891 in words is "nine million, nine hundred fifty-eight thousand, eight hundred ninety-one".