1211021011220 has 24 divisors (see below), whose sum is σ = 2550228105600. Its totient is φ = 483059074592.

The previous prime is 1211021011199. The next prime is 1211021011229. The reversal of 1211021011220 is 221101201121.

It is a super-2 number, since 2×1211021011220² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1211021011195 and 1211021011204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211021011229) 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, 84325760 + ... + 84340119.

It is an arithmetic number, because the mean of its divisors is an integer number (106259504400).

Almost surely, 2^{1211021011220} is an apocalyptic number.

1211021011220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211021011220 is an abundant number, since it is smaller than the sum of its proper divisors (1339207094380).

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

1211021011220 is a wasteful number, since it uses less digits than its factorization.

1211021011220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168666247 (or 168666245 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1211021011220 its reverse (221101201121), we get a palindrome (1432122212341).

The spelling of 1211021011220 in words is "one trillion, two hundred eleven billion, twenty-one million, eleven thousand, two hundred twenty".