221142421236 has 72 divisors (see below), whose sum is σ = 567433655712. Its totient is φ = 66981992000.

The previous prime is 221142421169. The next prime is 221142421249. The reversal of 221142421236 is 632124241122.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 3222886 + ... + 3290786.

It is an arithmetic number, because the mean of its divisors is an integer number (7881022996).

Almost surely, 2^221142421236 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 221142421236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283716827856).

221142421236 is an abundant number, since it is smaller than the sum of its proper divisors (346291234476).

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

221142421236 is a wasteful number, since it uses less digits than its factorization.

221142421236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70173 (or 70160 counting only the distinct ones).

The product of its digits is 9216, while the sum is 30.

Adding to 221142421236 its reverse (632124241122), we get a palindrome (853266662358).

The spelling of 221142421236 in words is "two hundred twenty-one billion, one hundred forty-two million, four hundred twenty-one thousand, two hundred thirty-six".