197721216 has 256 divisors, whose sum is σ = 728524800. Its totient is φ = 51287040.

The previous prime is 197721197. The next prime is 197721233. The reversal of 197721216 is 612127791.

It is a happy number.

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

It is a nude number because it is divisible by every one of its digits.

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 31 ways as a sum of consecutive naturals, for example, 265741 + ... + 266483.

It is an arithmetic number, because the mean of its divisors is an integer number (2845800).

Almost surely, 2^197721216 is an apocalyptic number.

197721216 is a gapful number since it is divisible by the number (16) 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 197721216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (364262400).

197721216 is an abundant number, since it is smaller than the sum of its proper divisors (530803584).

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

197721216 is a wasteful number, since it uses less digits than its factorization.

197721216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784 (or 766 counting only the distinct ones).

The product of its digits is 10584, while the sum is 36.

The square root of 197721216 is about 14061.3376319609. The cubic root of 197721216 is about 582.5739899996.

The spelling of 197721216 in words is "one hundred ninety-seven million, seven hundred twenty-one thousand, two hundred sixteen".