221221432240 has 80 divisors (see below), whose sum is σ = 515501157600. Its totient is φ = 88289058816.

The previous prime is 221221432219. The next prime is 221221432261. The reversal of 221221432240 is 42234122122.

It is an interprime number because it is at equal distance from previous prime (221221432219) and next prime (221221432261).

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

It is a super-2 number, since 2×221221432240² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106202239 + ... + 106204321.

It is an arithmetic number, because the mean of its divisors is an integer number (6443764470).

Almost surely, 2^221221432240 is an apocalyptic number.

221221432240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221432240 is an abundant number, since it is smaller than the sum of its proper divisors (294279725360).

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

221221432240 is a wasteful number, since it uses less digits than its factorization.

221221432240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4454 (or 4448 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 221221432240 its reverse (42234122122), we get a palindrome (263455554362).

The spelling of 221221432240 in words is "two hundred twenty-one billion, two hundred twenty-one million, four hundred thirty-two thousand, two hundred forty".