211221221000000 has 392 divisors, whose sum is σ = 527740454991960. Its totient is φ = 83874995200000.

The previous prime is 211221220999981. The next prime is 211221221000059. The reversal of 211221221000000 is 122122112.

It can be written as a sum of positive squares in 28 ways, for example, as 9803361385024 + 201417859614976 = 3131032^2 + 14192176^2 .

It is a super-2 number, since 2×211221221000000² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 85272998762 + ... + 85273001238.

Almost surely, 2^{211221221000000} is an apocalyptic number.

211221221000000 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 211221221000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263870227495980).

211221221000000 is an abundant number, since it is smaller than the sum of its proper divisors (316519233991960).

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

211221221000000 is an frugal number, since it uses more digits than its factorization.

211221221000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3105 (or 3070 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 211221221000000 its reverse (122122112), we get a palindrome (211221343122112).

It can be divided in two parts, 21122122 and 1000000, that added together give a palindrome (22122122).

The spelling of 211221221000000 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twenty-one million", and thus it is an aban number.