221221201340 has 24 divisors (see below), whose sum is σ = 464601599280. Its totient is φ = 88481418368.

The previous prime is 221221201339. The next prime is 221221201349. The reversal of 221221201340 is 43102122122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221201349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180770 + ... + 689289.

It is an arithmetic number, because the mean of its divisors is an integer number (19358399970).

Almost surely, 2^221221201340 is an apocalyptic number.

221221201340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221201340 is an abundant number, since it is smaller than the sum of its proper divisors (243380397940).

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

221221201340 is a wasteful number, since it uses less digits than its factorization.

221221201340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 882781 (or 882779 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 221221201340 its reverse (43102122122), we get a palindrome (264323323462).

The spelling of 221221201340 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred one thousand, three hundred forty".