2001211101 has 6 divisors (see below), whose sum is σ = 2890638270. Its totient is φ = 1334140728.

The previous prime is 2001211097. The next prime is 2001211109. The reversal of 2001211101 is 1011121002.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1960187076 + 41024025 = 44274^2 + 6405^2 .

It is not a de Polignac number, because 2001211101 - 2² = 2001211097 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 222356789 = 2001211101 / (2 + 0 + 0 + 1 + 2 + 1 + 1 + 1 + 0 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001211109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 111178386 + ... + 111178403.

It is an arithmetic number, because the mean of its divisors is an integer number (481773045).

Almost surely, 2^2001211101 is an apocalyptic number.

It is an amenable number.

2001211101 is a deficient number, since it is larger than the sum of its proper divisors (889427169).

2001211101 is a wasteful number, since it uses less digits than its factorization.

2001211101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222356795 (or 222356792 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 2001211101 is about 44734.8980215670. The cubic root of 2001211101 is about 1260.1753138525.

Adding to 2001211101 its reverse (1011121002), we get a palindrome (3012332103).

Subtracting from 2001211101 its reverse (1011121002), we obtain a palindrome (990090099).

It can be divided in two parts, 20012 and 11101, that added together give a palindrome (31113).

The spelling of 2001211101 in words is "two billion, one million, two hundred eleven thousand, one hundred one".