1011211221121 has 4 divisors (see below), whose sum is σ = 1016860446000. Its totient is φ = 1005561996244.

The previous prime is 1011211221043. The next prime is 1011211221127. The reversal of 1011211221121 is 1211221121101.

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 1011211221121 - 2⁷ = 1011211220993 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011211221095 and 1011211221104.

It is not an unprimeable number, because it can be changed into a prime (1011211221127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2824612171 + ... + 2824612528.

It is an arithmetic number, because the mean of its divisors is an integer number (254215111500).

Almost surely, 2^{1011211221121} is an apocalyptic number.

It is an amenable number.

1011211221121 is a deficient number, since it is larger than the sum of its proper divisors (5649224879).

1011211221121 is an equidigital number, since it uses as much as digits as its factorization.

1011211221121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5649224878.

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

Adding to 1011211221121 its reverse (1211221121101), we get a palindrome (2222432342222).

It can be divided in two parts, 101 and 1211221121, that multiplied together give a palindrome (122333333221).

The spelling of 1011211221121 in words is "one trillion, eleven billion, two hundred eleven million, two hundred twenty-one thousand, one hundred twenty-one".