1211001122121 has 16 divisors (see below), whose sum is σ = 1854080713728. Its totient is φ = 688721014800.

The previous prime is 1211001122083. The next prime is 1211001122141. The reversal of 1211001122121 is 1212211001121.

It is a happy number.

It is not a de Polignac number, because 1211001122121 - 2²¹ = 1210999024969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211001122121.

It is not an unprimeable number, because it can be changed into a prime (1211001122141) 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, 136646565 + ... + 136655426.

It is an arithmetic number, because the mean of its divisors is an integer number (115880044608).

Almost surely, 2^{1211001122121} is an apocalyptic number.

It is an amenable number.

1211001122121 is a deficient number, since it is larger than the sum of its proper divisors (643079591607).

1211001122121 is a wasteful number, since it uses less digits than its factorization.

1211001122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273302212.

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

Adding to 1211001122121 its reverse (1212211001121), we get a palindrome (2423212123242).

The spelling of 1211001122121 in words is "one trillion, two hundred eleven billion, one million, one hundred twenty-two thousand, one hundred twenty-one".