1211120121121 has 4 divisors (see below), whose sum is σ = 1211124545712. Its totient is φ = 1211115696532.

The previous prime is 1211120121083. The next prime is 1211120121137. The reversal of 1211120121121 is 1211210211121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1211120121121 - 2¹⁹ = 1211119596833 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211120121095 and 1211120121104.

It is not an unprimeable number, because it can be changed into a prime (1211120121521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1772575 + ... + 2358868.

It is an arithmetic number, because the mean of its divisors is an integer number (302781136428).

Almost surely, 2^{1211120121121} is an apocalyptic number.

It is an amenable number.

1211120121121 is a deficient number, since it is larger than the sum of its proper divisors (4424591).

1211120121121 is an equidigital number, since it uses as much as digits as its factorization.

1211120121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4424590.

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

Adding to 1211120121121 its reverse (1211210211121), we get a palindrome (2422330332242).

The spelling of 1211120121121 in words is "one trillion, two hundred eleven billion, one hundred twenty million, one hundred twenty-one thousand, one hundred twenty-one".