221111010000 has 450 divisors, whose sum is σ = 821515110702. Its totient is φ = 55488000000.

The previous prime is 221111009971. The next prime is 221111010079. The reversal of 221111010000 is 10111122.

It is a happy number.

It can be written as a sum of positive squares in 15 ways, for example, as 215645069376 + 5465940624 = 464376^2 + 73932^2 .

It is a tau number, because it is divible by the number of its divisors (450).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 26005750 + ... + 26014250.

Almost surely, 2^221111010000 is an apocalyptic number.

221111010000 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 221111010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (410757555351).

221111010000 is an abundant number, since it is smaller than the sum of its proper divisors (600404100702).

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

221111010000 is a wasteful number, since it uses less digits than its factorization.

221111010000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8569 (or 8528 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 221111010000 its reverse (10111122), we get a palindrome (221121121122).

The spelling of 221111010000 in words is "two hundred twenty-one billion, one hundred eleven million, ten thousand".