221423375844 has 144 divisors (see below), whose sum is σ = 635736681216. Its totient is φ = 66829860000.

The previous prime is 221423375801. The next prime is 221423375851. The reversal of 221423375844 is 448573324122.

221423375844 is a `hidden beast` number, since 2 + 2 + 14 + 23 + 37 + 584 + 4 = 666.

It is a super-2 number, since 2×221423375844² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221423375844.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2642439 + ... + 2724945.

It is an arithmetic number, because the mean of its divisors is an integer number (4414838064).

Almost surely, 2^221423375844 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 221423375844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317868340608).

221423375844 is an abundant number, since it is smaller than the sum of its proper divisors (414313305372).

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

221423375844 is a wasteful number, since it uses less digits than its factorization.

221423375844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82788 (or 82774 counting only the distinct ones).

The product of its digits is 1290240, while the sum is 45.

Adding to 221423375844 its reverse (448573324122), we get a palindrome (669996699966).

The spelling of 221423375844 in words is "two hundred twenty-one billion, four hundred twenty-three million, three hundred seventy-five thousand, eight hundred forty-four".