9971839 has 2 divisors, whose sum is σ = 9971840. Its totient is φ = 9971838.

The previous prime is 9971837. The next prime is 9971861. The reversal of 9971839 is 9381799.

9971839 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9971839 - 2¹ = 9971837 is a prime.

Together with 9971837, it forms a pair of twin primes.

9971839 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9971837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4985919 + 4985920.

It is an arithmetic number, because the mean of its divisors is an integer number (4985920).

Almost surely, 2^9971839 is an apocalyptic number.

9971839 is a deficient number, since it is larger than the sum of its proper divisors (1).

9971839 is an equidigital number, since it uses as much as digits as its factorization.

9971839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 122472, while the sum is 46.

The square root of 9971839 is about 3157.8218759138. The cubic root of 9971839 is about 215.2410420816.

The spelling of 9971839 in words is "nine million, nine hundred seventy-one thousand, eight hundred thirty-nine".