211221221011220 has 24 divisors (see below), whose sum is σ = 506930930427264. Its totient is φ = 72418704346656.

The previous prime is 211221221011211. The next prime is 211221221011223. The reversal of 211221221011220 is 22110122122112.

It is a super-2 number, since 2×211221221011220² (a number of 29 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 211221221011192 and 211221221011201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221221011223) 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, 754361503472 + ... + 754361503751.

It is an arithmetic number, because the mean of its divisors is an integer number (21122122101136).

Almost surely, 2^{211221221011220} is an apocalyptic number.

211221221011220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211221221011220 is an abundant number, since it is smaller than the sum of its proper divisors (295709709416044).

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

211221221011220 is a wasteful number, since it uses less digits than its factorization.

211221221011220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1508723007239 (or 1508723007237 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 211221221011220 its reverse (22110122122112), we get a palindrome (233331343133332).

The spelling of 211221221011220 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twenty-one million, eleven thousand, two hundred twenty".