221545355723720 has 192 divisors, whose sum is σ = 580312212364800. Its totient is φ = 75899332454400.

The previous prime is 221545355723711. The next prime is 221545355723729. The reversal of 221545355723720 is 27327553545122.

221545355723720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221545355723711) and next prime (221545355723729).

It is not an unprimeable number, because it can be changed into a prime (221545355723729) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25310786864 + ... + 25310795616.

It is an arithmetic number, because the mean of its divisors is an integer number (3022459439400).

Almost surely, 2^{221545355723720} is an apocalyptic number.

221545355723720 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 221545355723720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (290156106182400).

221545355723720 is an abundant number, since it is smaller than the sum of its proper divisors (358766856641080).

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

221545355723720 is a wasteful number, since it uses less digits than its factorization.

221545355723720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17348 (or 17337 counting only the distinct ones).

The product of its (nonzero) digits is 17640000, while the sum is 53.

The spelling of 221545355723720 in words is "two hundred twenty-one trillion, five hundred forty-five billion, three hundred fifty-five million, seven hundred twenty-three thousand, seven hundred twenty".