197821440000 has 980 divisors, whose sum is σ = 755193749706. Its totient is φ = 51757056000.

The previous prime is 197821439951. The next prime is 197821440077. The reversal of 197821440000 is 44128791.

197821440000 is a `hidden beast` number, since 197 + 8 + 21 + 440 + 0 + 0 + 0 = 666.

It can be written as a sum of positive squares in 5 ways, for example, as 9701462016 + 188119977984 = 98496^2 + 433728^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 69 ways as a sum of consecutive naturals, for example, 3732479974 + ... + 3732480026.

Almost surely, 2^197821440000 is an apocalyptic number.

197821440000 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 197821440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (377596874853).

197821440000 is an abundant number, since it is smaller than the sum of its proper divisors (557372309706).

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

197821440000 is an frugal number, since it uses more digits than its factorization.

197821440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

Adding to 197821440000 its reverse (44128791), we get a palindrome (197865568791).

The spelling of 197821440000 in words is "one hundred ninety-seven billion, eight hundred twenty-one million, four hundred forty thousand".