198136221840 has 240 divisors, whose sum is σ = 681903913392. Its totient is φ = 51538046976.

The previous prime is 198136221823. The next prime is 198136221853. The reversal of 198136221840 is 48122631891.

198136221840 is a `hidden beast` number, since 1 + 9 + 8 + 1 + 3 + 622 + 18 + 4 + 0 = 666.

198136221840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 2181263616 + 195954958224 = 46704^2 + 442668^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-3 number, since 3×198136221840³ (a number of 35 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6586674 + ... + 6616686.

Almost surely, 2^198136221840 is an apocalyptic number.

198136221840 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 198136221840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (340951956696).

198136221840 is an abundant number, since it is smaller than the sum of its proper divisors (483767691552).

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

198136221840 is a wasteful number, since it uses less digits than its factorization.

198136221840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30258 (or 30249 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 198136221840 in words is "one hundred ninety-eight billion, one hundred thirty-six million, two hundred twenty-one thousand, eight hundred forty".