2215172261 has 2 divisors, whose sum is σ = 2215172262. Its totient is φ = 2215172260.

The previous prime is 2215172243. The next prime is 2215172269. The reversal of 2215172261 is 1622715122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2145449761 + 69722500 = 46319^2 + 8350^2 .

It is a cyclic number.

It is not a de Polignac number, because 2215172261 - 2¹⁰ = 2215171237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2215172269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1107586130 + 1107586131.

It is an arithmetic number, because the mean of its divisors is an integer number (1107586131).

Almost surely, 2^2215172261 is an apocalyptic number.

It is an amenable number.

2215172261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2215172261 is an equidigital number, since it uses as much as digits as its factorization.

2215172261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 29.

The square root of 2215172261 is about 47065.6165475392. The cubic root of 2215172261 is about 1303.5744352348.

Adding to 2215172261 its reverse (1622715122), we get a palindrome (3837887383).

The spelling of 2215172261 in words is "two billion, two hundred fifteen million, one hundred seventy-two thousand, two hundred sixty-one".