221000001424 has 90 divisors (see below), whose sum is σ = 450180750390. Its totient is φ = 105097559040.

The previous prime is 221000001419. The next prime is 221000001449. The reversal of 221000001424 is 424100000122.

It can be written as a sum of positive squares in only one way, i.e., 192685881600 + 28314119824 = 438960^2 + 168268^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 221000001398 and 221000001407.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 53521792 + ... + 53525920.

Almost surely, 2^221000001424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221000001424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225090375195).

221000001424 is an abundant number, since it is smaller than the sum of its proper divisors (229180748966).

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

221000001424 is an equidigital number, since it uses as much as digits as its factorization.

221000001424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4317 (or 4221 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 221000001424 its reverse (424100000122), we get a palindrome (645100001546).

The spelling of 221000001424 in words is "two hundred twenty-one billion, one thousand, four hundred twenty-four".