221311031240 has 128 divisors (see below), whose sum is σ = 544721224320. Its totient is φ = 80426649600.

The previous prime is 221311031239. The next prime is 221311031257. The reversal of 221311031240 is 42130113122.

221311031240 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59957795 + ... + 59961485.

It is an arithmetic number, because the mean of its divisors is an integer number (4255634565).

Almost surely, 2^221311031240 is an apocalyptic number.

221311031240 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 221311031240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (272360612160).

221311031240 is an abundant number, since it is smaller than the sum of its proper divisors (323410193080).

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

221311031240 is a wasteful number, since it uses less digits than its factorization.

221311031240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5503 (or 5499 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 221311031240 its reverse (42130113122), we get a palindrome (263441144362).

The spelling of 221311031240 in words is "two hundred twenty-one billion, three hundred eleven million, thirty-one thousand, two hundred forty".