1001122211121 has 16 divisors (see below), whose sum is σ = 1352121685824. Its totient is φ = 658783174464.

The previous prime is 1001122211099. The next prime is 1001122211137. The reversal of 1001122211121 is 1211122211001.

It is a happy number.

It is not a de Polignac number, because 1001122211121 - 2⁶ = 1001122211057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1001122211121.

It is not an unprimeable number, because it can be changed into a prime (1001122211191) 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, 1521586 + ... + 2077851.

It is an arithmetic number, because the mean of its divisors is an integer number (84507605364).

Almost surely, 2^{1001122211121} is an apocalyptic number.

It is an amenable number.

1001122211121 is a deficient number, since it is larger than the sum of its proper divisors (350999474703).

1001122211121 is a wasteful number, since it uses less digits than its factorization.

1001122211121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3600640.

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

Adding to 1001122211121 its reverse (1211122211001), we get a palindrome (2212244422122).

The spelling of 1001122211121 in words is "one trillion, one billion, one hundred twenty-two million, two hundred eleven thousand, one hundred twenty-one".