221221211020000 has 240 divisors, whose sum is σ = 549730987898400. Its totient is φ = 87595603200000.

The previous prime is 221221211019953. The next prime is 221221211020009. The reversal of 221221211020000 is 20112122122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221211020009) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20278774546 + ... + 20278785454.

It is an arithmetic number, because the mean of its divisors is an integer number (2290545782910).

Almost surely, 2^{221221211020000} is an apocalyptic number.

221221211020000 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 221221211020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274865493949200).

221221211020000 is an abundant number, since it is smaller than the sum of its proper divisors (328509776878400).

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

221221211020000 is a wasteful number, since it uses less digits than its factorization.

221221211020000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21079 (or 21056 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221221211020000 its reverse (20112122122), we get a palindrome (221241323142122).

The spelling of 221221211020000 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, two hundred eleven million, twenty thousand".