2195621081 has 2 divisors, whose sum is σ = 2195621082. Its totient is φ = 2195621080.

The previous prime is 2195621041. The next prime is 2195621083. The reversal of 2195621081 is 1801265912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1902355456 + 293265625 = 43616^2 + 17125^2 .

It is a cyclic number.

It is not a de Polignac number, because 2195621081 - 2⁶ = 2195621017 is a prime.

It is a super-2 number, since 2×2195621081² = 9641503862663217122, which contains 22 as substring.

Together with 2195621083, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2195621083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1097810540 + 1097810541.

It is an arithmetic number, because the mean of its divisors is an integer number (1097810541).

Almost surely, 2^2195621081 is an apocalyptic number.

It is an amenable number.

2195621081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2195621081 is an equidigital number, since it uses as much as digits as its factorization.

2195621081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 2195621081 is about 46857.4549138128. The cubic root of 2195621081 is about 1299.7279669452.

Adding to 2195621081 its reverse (1801265912), we get a palindrome (3996886993).

The spelling of 2195621081 in words is "two billion, one hundred ninety-five million, six hundred twenty-one thousand, eighty-one".