198140391 has 16 divisors (see below), whose sum is σ = 299788800. Its totient is φ = 129282264.

The previous prime is 198140381. The next prime is 198140399. The reversal of 198140391 is 193041891.

It is not a de Polignac number, because 198140391 - 2⁵ = 198140359 is a prime.

It is a super-3 number, since 3×198140391³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198140399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76801 + ... + 79338.

It is an arithmetic number, because the mean of its divisors is an integer number (18736800).

Almost surely, 2^198140391 is an apocalyptic number.

198140391 is a deficient number, since it is larger than the sum of its proper divisors (101648409).

198140391 is a wasteful number, since it uses less digits than its factorization.

198140391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156195 (or 156189 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 198140391 is about 14076.2349724633. The cubic root of 198140391 is about 582.9853909430.

The spelling of 198140391 in words is "one hundred ninety-eight million, one hundred forty thousand, three hundred ninety-one".