198409540 has 48 divisors (see below), whose sum is σ = 489065472. Its totient is φ = 66185856.

The previous prime is 198409531. The next prime is 198409543. The reversal of 198409540 is 45904891.

It is a junction number, because it is equal to n+sod(n) for n = 198409493 and 198409502.

It is not an unprimeable number, because it can be changed into a prime (198409543) 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, 13972 + ... + 24331.

It is an arithmetic number, because the mean of its divisors is an integer number (10188864).

Almost surely, 2^198409540 is an apocalyptic number.

198409540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

198409540 is an abundant number, since it is smaller than the sum of its proper divisors (290655932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

198409540 is a wasteful number, since it uses less digits than its factorization.

198409540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38356 (or 38354 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 198409540 is about 14085.7921325000. The cubic root of 198409540 is about 583.2492424816.

The spelling of 198409540 in words is "one hundred ninety-eight million, four hundred nine thousand, five hundred forty".