2121111101 has 4 divisors (see below), whose sum is σ = 2144943900. Its totient is φ = 2097278304.

The previous prime is 2121111077. The next prime is 2121111121. The reversal of 2121111101 is 1011111212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 565203076 + 1555908025 = 23774^2 + 39445^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121111101 - 2³⁰ = 1047369277 is a prime.

It is a super-2 number, since 2×2121111101² = 8998224605570864402, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121111121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11916266 + ... + 11916443.

It is an arithmetic number, because the mean of its divisors is an integer number (536235975).

Almost surely, 2^2121111101 is an apocalyptic number.

It is an amenable number.

2121111101 is a deficient number, since it is larger than the sum of its proper divisors (23832799).

2121111101 is an equidigital number, since it uses as much as digits as its factorization.

2121111101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23832798.

The product of its (nonzero) digits is 4, while the sum is 11.

The square root of 2121111101 is about 46055.5219381998. The cubic root of 2121111101 is about 1284.8560454847.

Adding to 2121111101 its reverse (1011111212), we get a palindrome (3132222313).

It can be divided in two parts, 2121111 and 101, that added together give a palindrome (2121212).

The spelling of 2121111101 in words is "two billion, one hundred twenty-one million, one hundred eleven thousand, one hundred one".