9847921 has 2 divisors, whose sum is σ = 9847922. Its totient is φ = 9847920.

The previous prime is 9847897. The next prime is 9847927. The reversal of 9847921 is 1297489.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6477025 + 3370896 = 2545^2 + 1836^2 .

It is a cyclic number.

It is not a de Polignac number, because 9847921 - 2⁵ = 9847889 is a prime.

It is a Chen prime.

9847921 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (9847927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4923960 + 4923961.

It is an arithmetic number, because the mean of its divisors is an integer number (4923961).

Almost surely, 2^9847921 is an apocalyptic number.

It is an amenable number.

9847921 is a deficient number, since it is larger than the sum of its proper divisors (1).

9847921 is an equidigital number, since it uses as much as digits as its factorization.

9847921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 40.

The square root of 9847921 is about 3138.1397355758. The cubic root of 9847921 is about 214.3457377461.

The spelling of 9847921 in words is "nine million, eight hundred forty-seven thousand, nine hundred twenty-one".