221245400000 has 168 divisors, whose sum is σ = 550676441952. Its totient is φ = 88188800000.

The previous prime is 221245399993. The next prime is 221245400011. The reversal of 221245400000 is 4542122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62198222 + ... + 62201778.

It is an arithmetic number, because the mean of its divisors is an integer number (3277835964).

Almost surely, 2^221245400000 is an apocalyptic number.

221245400000 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 221245400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (275338220976).

221245400000 is an abundant number, since it is smaller than the sum of its proper divisors (329431041952).

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

221245400000 is an frugal number, since it uses more digits than its factorization.

221245400000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3905 (or 3875 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

Adding to 221245400000 its reverse (4542122), we get a palindrome (221249942122).

The spelling of 221245400000 in words is "two hundred twenty-one billion, two hundred forty-five million, four hundred thousand".