1211210021121 has 16 divisors (see below), whose sum is σ = 1615761143040. Its totient is φ = 807066234000.

The previous prime is 1211210021059. The next prime is 1211210021137. The reversal of 1211210021121 is 1211200121121.

It is a happy number.

It is not a de Polignac number, because 1211210021121 - 2⁶ = 1211210021057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211210021121.

It is not an unprimeable number, because it can be changed into a prime (1211210021221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70398306 + ... + 70415508.

It is an arithmetic number, because the mean of its divisors is an integer number (100985071440).

Almost surely, 2^{1211210021121} is an apocalyptic number.

It is an amenable number.

1211210021121 is a deficient number, since it is larger than the sum of its proper divisors (404551121919).

1211210021121 is a wasteful number, since it uses less digits than its factorization.

1211210021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27676.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1211210021121 its reverse (1211200121121), we get a palindrome (2422410142242).

The spelling of 1211210021121 in words is "one trillion, two hundred eleven billion, two hundred ten million, twenty-one thousand, one hundred twenty-one".