221221224240 has 80 divisors (see below), whose sum is σ = 686104750176. Its totient is φ = 58964889600.

The previous prime is 221221224227. The next prime is 221221224253. The reversal of 221221224240 is 42422122122.

It is an interprime number because it is at equal distance from previous prime (221221224227) and next prime (221221224253).

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

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 221221224240.

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, 305370 + ... + 731910.

Almost surely, 2^221221224240 is an apocalyptic number.

221221224240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221224240 is an abundant number, since it is smaller than the sum of its proper divisors (464883525936).

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

221221224240 is a wasteful number, since it uses less digits than its factorization.

221221224240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428718 (or 428712 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

Adding to 221221224240 its reverse (42422122122), we get a palindrome (263643346362).

The spelling of 221221224240 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred twenty-four thousand, two hundred forty".