211221175441728 has 224 divisors, whose sum is σ = 607771475539200. Its totient is φ = 64469324169216.

The previous prime is 211221175441709. The next prime is 211221175441729. The reversal of 211221175441728 is 827144571122112.

It is a super-2 number, since 2×211221175441728² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221175441729) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1665206533 + ... + 1665333371.

It is an arithmetic number, because the mean of its divisors is an integer number (2713265515800).

Almost surely, 2^{211221175441728} 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 211221175441728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303885737769600).

211221175441728 is an abundant number, since it is smaller than the sum of its proper divisors (396550300097472).

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

211221175441728 is a wasteful number, since it uses less digits than its factorization.

211221175441728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140697 (or 140687 counting only the distinct ones).

The product of its digits is 501760, while the sum is 48.

The spelling of 211221175441728 in words is "two hundred eleven trillion, two hundred twenty-one billion, one hundred seventy-five million, four hundred forty-one thousand, seven hundred twenty-eight".