9809945 has 4 divisors (see below), whose sum is σ = 11771940. Its totient is φ = 7847952.

The previous prime is 9809941. The next prime is 9809971. The reversal of 9809945 is 5499089.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5499089 = 61 ⋅90149.

It can be written as a sum of positive squares in 2 ways, for example, as 2611456 + 7198489 = 1616^2 + 2683^2 .

It is a cyclic number.

It is not a de Polignac number, because 9809945 - 2² = 9809941 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9809896 and 9809905.

It is not an unprimeable number, because it can be changed into a prime (9809941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 980990 + ... + 980999.

It is an arithmetic number, because the mean of its divisors is an integer number (2942985).

Almost surely, 2^9809945 is an apocalyptic number.

It is an amenable number.

9809945 is a deficient number, since it is larger than the sum of its proper divisors (1961995).

9809945 is a wasteful number, since it uses less digits than its factorization.

9809945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961994.

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 9809945 is about 3132.0831725866. The cubic root of 9809945 is about 214.0698595690.

The spelling of 9809945 in words is "nine million, eight hundred nine thousand, nine hundred forty-five".