221426340 has 96 divisors (see below), whose sum is σ = 637459200. Its totient is φ = 57408000.

The previous prime is 221426327. The next prime is 221426341. The reversal of 221426340 is 43624122.

It is a self number, because there is not a number n which added to its sum of digits gives 221426340.

It is not an unprimeable number, because it can be changed into a prime (221426341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 369361 + ... + 369959.

It is an arithmetic number, because the mean of its divisors is an integer number (6640200).

Almost surely, 2^221426340 is an apocalyptic number.

221426340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221426340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318729600).

221426340 is an abundant number, since it is smaller than the sum of its proper divisors (416032860).

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

221426340 is a wasteful number, since it uses less digits than its factorization.

221426340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 773 (or 771 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 221426340 is about 14880.4012042687. The cubic root of 221426340 is about 604.9828923059.

It can be divided in two parts, 22142 and 6340, that added together give a palindrome (28482).

The spelling of 221426340 in words is "two hundred twenty-one million, four hundred twenty-six thousand, three hundred forty".