2101222261 has 2 divisors, whose sum is σ = 2101222262. Its totient is φ = 2101222260.

The previous prime is 2101222199. The next prime is 2101222307. The reversal of 2101222261 is 1622221012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2069795025 + 31427236 = 45495^2 + 5606^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101222261 - 2²⁵ = 2067667829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2101222861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050611130 + 1050611131.

It is an arithmetic number, because the mean of its divisors is an integer number (1050611131).

Almost surely, 2^2101222261 is an apocalyptic number.

It is an amenable number.

2101222261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101222261 is an equidigital number, since it uses as much as digits as its factorization.

2101222261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 2101222261 is about 45839.0909704806. The cubic root of 2101222261 is about 1280.8275615597.

Adding to 2101222261 its reverse (1622221012), we get a palindrome (3723443273).

The spelling of 2101222261 in words is "two billion, one hundred one million, two hundred twenty-two thousand, two hundred sixty-one".