1211010121220 has 48 divisors (see below), whose sum is σ = 2651149218816. Its totient is φ = 464136720000.

The previous prime is 1211010121171. The next prime is 1211010121229. The reversal of 1211010121220 is 221210101121.

It is a junction number, because it is equal to n+sod(n) for n = 1211010121195 and 1211010121204.

It is not an unprimeable number, because it can be changed into a prime (1211010121229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9606896 + ... + 9732135.

It is an arithmetic number, because the mean of its divisors is an integer number (55232275392).

Almost surely, 2^{1211010121220} is an apocalyptic number.

1211010121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211010121220 is an abundant number, since it is smaller than the sum of its proper divisors (1440139097596).

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

1211010121220 is a wasteful number, since it uses less digits than its factorization.

1211010121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19339172 (or 19339170 counting only the distinct ones).

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

Adding to 1211010121220 its reverse (221210101121), we get a palindrome (1432220222341).

The spelling of 1211010121220 in words is "one trillion, two hundred eleven billion, ten million, one hundred twenty-one thousand, two hundred twenty".