9945391 has 4 divisors (see below), whose sum is σ = 10530432. Its totient is φ = 9360352.

The previous prime is 9945359. The next prime is 9945409. The reversal of 9945391 is 1935499.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1935499 = 353 ⋅5483.

It is a cyclic number.

It is not a de Polignac number, because 9945391 - 2⁵ = 9945359 is a prime.

It is a Duffinian number.

9945391 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9942391) 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 in 3 ways as a sum of consecutive naturals, for example, 292495 + ... + 292528.

It is an arithmetic number, because the mean of its divisors is an integer number (2632608).

Almost surely, 2^9945391 is an apocalyptic number.

9945391 is a deficient number, since it is larger than the sum of its proper divisors (585041).

9945391 is a wasteful number, since it uses less digits than its factorization.

9945391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 585040.

The product of its digits is 43740, while the sum is 40.

The square root of 9945391 is about 3153.6313988797. The cubic root of 9945391 is about 215.0505812127.

The spelling of 9945391 in words is "nine million, nine hundred forty-five thousand, three hundred ninety-one".