2102111261 has 4 divisors (see below), whose sum is σ = 2102207232. Its totient is φ = 2102015292.

The previous prime is 2102111191. The next prime is 2102111267. The reversal of 2102111261 is 1621112012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2102111261 - 2¹⁰ = 2102110237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2102111267) 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, 2756 + ... + 64898.

It is an arithmetic number, because the mean of its divisors is an integer number (525551808).

Almost surely, 2^2102111261 is an apocalyptic number.

It is an amenable number.

2102111261 is a deficient number, since it is larger than the sum of its proper divisors (95971).

2102111261 is an equidigital number, since it uses as much as digits as its factorization.

2102111261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95970.

The product of its (nonzero) digits is 48, while the sum is 17.

The square root of 2102111261 is about 45848.7869087068. The cubic root of 2102111261 is about 1281.0081699572.

Adding to 2102111261 its reverse (1621112012), we get a palindrome (3723223273).

The spelling of 2102111261 in words is "two billion, one hundred two million, one hundred eleven thousand, two hundred sixty-one".