211221142440 has 1024 divisors, whose sum is σ = 846028800000. Its totient is φ = 41771520000.

The previous prime is 211221142283. The next prime is 211221142469. The reversal of 211221142440 is 44241122112.

It is a happy number.

211221142440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×211221142440² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 211221142440.

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 255 ways as a sum of consecutive naturals, for example, 1417591486 + ... + 1417591634.

It is an arithmetic number, because the mean of its divisors is an integer number (826200000).

Almost surely, 2^211221142440 is an apocalyptic number.

211221142440 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 211221142440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (423014400000).

211221142440 is an abundant number, since it is smaller than the sum of its proper divisors (634807657560).

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

211221142440 is a wasteful number, since it uses less digits than its factorization.

211221142440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 24.

Adding to 211221142440 its reverse (44241122112), we get a palindrome (255462264552).

The spelling of 211221142440 in words is "two hundred eleven billion, two hundred twenty-one million, one hundred forty-two thousand, four hundred forty".