221720063440 has 80 divisors (see below), whose sum is σ = 517521787200. Its totient is φ = 88340668416.

The previous prime is 221720063429. The next prime is 221720063449. The reversal of 221720063440 is 44360027122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221720063449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26040624 + ... + 26049136.

It is an arithmetic number, because the mean of its divisors is an integer number (6469022340).

Almost surely, 2^221720063440 is an apocalyptic number.

221720063440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221720063440 is an abundant number, since it is smaller than the sum of its proper divisors (295801723760).

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

221720063440 is a wasteful number, since it uses less digits than its factorization.

221720063440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9764 (or 9758 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 31.

The spelling of 221720063440 in words is "two hundred twenty-one billion, seven hundred twenty million, sixty-three thousand, four hundred forty".