198512640 has 208 divisors, whose sum is σ = 707702400. Its totient is φ = 52789248.

The previous prime is 198512599. The next prime is 198512641. The reversal of 198512640 is 46215891.

198512640 is a `hidden beast` number, since 1 + 9 + 8 + 5 + 1 + 2 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 198512595 and 198512604.

It is not an unprimeable number, because it can be changed into a prime (198512641) 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, 552781 + ... + 553139.

Almost surely, 2^198512640 is an apocalyptic number.

198512640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 198512640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (353851200).

198512640 is an abundant number, since it is smaller than the sum of its proper divisors (509189760).

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

198512640 is an equidigital number, since it uses as much as digits as its factorization.

198512640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397 (or 369 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 198512640 is about 14089.4513732792. The cubic root of 198512640 is about 583.3502500310.

The spelling of 198512640 in words is "one hundred ninety-eight million, five hundred twelve thousand, six hundred forty".