221220122240420 has 48 divisors (see below), whose sum is σ = 471522954544320. Its totient is φ = 87162352573824.

The previous prime is 221220122240399. The next prime is 221220122240423. The reversal of 221220122240420 is 24042221022122.

It is a self number, because there is not a number n which added to its sum of digits gives 221220122240420.

It is not an unprimeable number, because it can be changed into a prime (221220122240423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18795902 + ... + 28208618.

It is an arithmetic number, because the mean of its divisors is an integer number (9823394886340).

Almost surely, 2^{221220122240420} is an apocalyptic number.

221220122240420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221220122240420 is an abundant number, since it is smaller than the sum of its proper divisors (250302832303900).

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

221220122240420 is a wasteful number, since it uses less digits than its factorization.

221220122240420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9430332 (or 9430330 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 26.

Adding to 221220122240420 its reverse (24042221022122), we get a palindrome (245262343262542).

The spelling of 221220122240420 in words is "two hundred twenty-one trillion, two hundred twenty billion, one hundred twenty-two million, two hundred forty thousand, four hundred twenty".