221500544240 has 40 divisors (see below), whose sum is σ = 520775172720. Its totient is φ = 87604706816.

The previous prime is 221500544207. The next prime is 221500544261. The reversal of 221500544240 is 42445005122.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15547694 + ... + 15561933.

It is an arithmetic number, because the mean of its divisors is an integer number (13019379318).

Almost surely, 2^221500544240 is an apocalyptic number.

221500544240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221500544240 is an abundant number, since it is smaller than the sum of its proper divisors (299274628480).

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

221500544240 is a wasteful number, since it uses less digits than its factorization.

221500544240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31109729 (or 31109723 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 29.

Adding to 221500544240 its reverse (42445005122), we get a palindrome (263945549362).

The spelling of 221500544240 in words is "two hundred twenty-one billion, five hundred million, five hundred forty-four thousand, two hundred forty".