9938198391 has 12 divisors (see below), whose sum is σ = 14565073656. Its totient is φ = 6023150320.

The previous prime is 9938198377. The next prime is 9938198423. The reversal of 9938198391 is 1938918399.

It is not a de Polignac number, because 9938198391 - 2¹¹ = 9938196343 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9938198371) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13688616 + ... + 13689341.

It is an arithmetic number, because the mean of its divisors is an integer number (1213756138).

Almost surely, 2^9938198391 is an apocalyptic number.

9938198391 is a deficient number, since it is larger than the sum of its proper divisors (4626875265).

9938198391 is a wasteful number, since it uses less digits than its factorization.

9938198391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27377982 (or 27377971 counting only the distinct ones).

The product of its digits is 3779136, while the sum is 60.

The square root of 9938198391 is about 99690.5130441207. The cubic root of 9938198391 is about 2149.9872644640.

The spelling of 9938198391 in words is "nine billion, nine hundred thirty-eight million, one hundred ninety-eight thousand, three hundred ninety-one".