221981135500 has 48 divisors (see below), whose sum is σ = 485309208384. Its totient is φ = 88700438400.

The previous prime is 221981135473. The next prime is 221981135543. The reversal of 221981135500 is 5531189122.

It is a self number, because there is not a number n which added to its sum of digits gives 221981135500.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 253944 + ... + 713056.

It is an arithmetic number, because the mean of its divisors is an integer number (10110608508).

Almost surely, 2^221981135500 is an apocalyptic number.

221981135500 is a gapful number since it is divisible by the number (20) 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 221981135500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242654604192).

221981135500 is an abundant number, since it is smaller than the sum of its proper divisors (263328072884).

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

221981135500 is a wasteful number, since it uses less digits than its factorization.

221981135500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460099 (or 460087 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 37.

The spelling of 221981135500 in words is "two hundred twenty-one billion, nine hundred eighty-one million, one hundred thirty-five thousand, five hundred".