9891945 has 48 divisors (see below), whose sum is σ = 20247552. Its totient is φ = 4371840.

The previous prime is 9891923. The next prime is 9891953. The reversal of 9891945 is 5491989.

9891945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9891945 - 2⁸ = 9891689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 9891945.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9259 + ... + 10271.

It is an arithmetic number, because the mean of its divisors is an integer number (421824).

Almost surely, 2^9891945 is an apocalyptic number.

It is an amenable number.

9891945 is an abundant number, since it is smaller than the sum of its proper divisors (10355607).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9891945 is a wasteful number, since it uses less digits than its factorization.

9891945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1062 (or 1059 counting only the distinct ones).

The product of its digits is 116640, while the sum is 45.

The square root of 9891945 is about 3145.1462605100. The cubic root of 9891945 is about 214.6646656428.

The spelling of 9891945 in words is "nine million, eight hundred ninety-one thousand, nine hundred forty-five".