1211100001101 has 144 divisors (see below), whose sum is σ = 1933192355328. Its totient is φ = 728946915840.

The previous prime is 1211100001091. The next prime is 1211100001121. The reversal of 1211100001101 is 1011000011121.

It is not a de Polignac number, because 1211100001101 - 2²¹ = 1211097903949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211100001121) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 3299999820 + ... + 3300000186.

It is an arithmetic number, because the mean of its divisors is an integer number (13424946912).

Almost surely, 2^{1211100001101} is an apocalyptic number.

It is an amenable number.

1211100001101 is a deficient number, since it is larger than the sum of its proper divisors (722092354227).

1211100001101 is a wasteful number, since it uses less digits than its factorization.

1211100001101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 824 (or 790 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 1211100001101 its reverse (1011000011121), we get a palindrome (2222100012222).

The spelling of 1211100001101 in words is "one trillion, two hundred eleven billion, one hundred million, one thousand, one hundred one".