1211121201220 has 48 divisors (see below), whose sum is σ = 2906757745920. Its totient is φ = 415232002944.

The previous prime is 1211121201211. The next prime is 1211121201263. The reversal of 1211121201220 is 221021211121.

It is a junction number, because it is equal to n+sod(n) for n = 1211121201194 and 1211121201203.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8914561 + ... + 9049399.

It is an arithmetic number, because the mean of its divisors is an integer number (60557453040).

Almost surely, 2^{1211121201220} is an apocalyptic number.

1211121201220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211121201220 is an abundant number, since it is smaller than the sum of its proper divisors (1695636544700).

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

1211121201220 is a wasteful number, since it uses less digits than its factorization.

1211121201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199012 (or 199010 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1211121201220 its reverse (221021211121), we get a palindrome (1432142412341).

Subtracting from 1211121201220 its reverse (221021211121), we obtain a palindrome (990099990099).

The spelling of 1211121201220 in words is "one trillion, two hundred eleven billion, one hundred twenty-one million, two hundred one thousand, two hundred twenty".