2101225681 has 2 divisors, whose sum is σ = 2101225682. Its totient is φ = 2101225680.

The previous prime is 2101225673. The next prime is 2101225691. The reversal of 2101225681 is 1865221012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2096815681 + 4410000 = 45791^2 + 2100^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101225681 - 2³ = 2101225673 is a prime.

It is a super-2 number, since 2×2101225681² = 8830298724987827522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2101225691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050612840 + 1050612841.

It is an arithmetic number, because the mean of its divisors is an integer number (1050612841).

Almost surely, 2^2101225681 is an apocalyptic number.

It is an amenable number.

2101225681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101225681 is an equidigital number, since it uses as much as digits as its factorization.

2101225681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 2101225681 is about 45839.1282748701. The cubic root of 2101225681 is about 1280.8282564612.

Adding to 2101225681 its reverse (1865221012), we get a palindrome (3966446693).

The spelling of 2101225681 in words is "two billion, one hundred one million, two hundred twenty-five thousand, six hundred eighty-one".