2210055721 has 2 divisors, whose sum is σ = 2210055722. Its totient is φ = 2210055720.

The previous prime is 2210055719. The next prime is 2210055739. The reversal of 2210055721 is 1275500122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1725571600 + 484484121 = 41540^2 + 22011^2 .

It is a cyclic number.

It is not a de Polignac number, because 2210055721 - 2¹ = 2210055719 is a prime.

Together with 2210055719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2210052721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1105027860 + 1105027861.

It is an arithmetic number, because the mean of its divisors is an integer number (1105027861).

Almost surely, 2^2210055721 is an apocalyptic number.

It is an amenable number.

2210055721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2210055721 is an equidigital number, since it uses as much as digits as its factorization.

2210055721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 2210055721 is about 47011.2297329053. The cubic root of 2210055721 is about 1302.5700088241.

Adding to 2210055721 its reverse (1275500122), we get a palindrome (3485555843).

The spelling of 2210055721 in words is "two billion, two hundred ten million, fifty-five thousand, seven hundred twenty-one".