8121434261 has 2 divisors, whose sum is σ = 8121434262. Its totient is φ = 8121434260.

The previous prime is 8121434257. The next prime is 8121434267. The reversal of 8121434261 is 1624341218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8121434161 + 100 = 90119^2 + 10^2 .

It is a cyclic number.

It is not a de Polignac number, because 8121434261 - 2² = 8121434257 is a prime.

It is a super-2 number, since 2×8121434261² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8121434267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4060717130 + 4060717131.

It is an arithmetic number, because the mean of its divisors is an integer number (4060717131).

Almost surely, 2^8121434261 is an apocalyptic number.

It is an amenable number.

8121434261 is a deficient number, since it is larger than the sum of its proper divisors (1).

8121434261 is an equidigital number, since it uses as much as digits as its factorization.

8121434261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 32.

The square root of 8121434261 is about 90119.0005548220. Note that the first 3 decimals coincide. The cubic root of 8121434261 is about 2010.0687468545.

Adding to 8121434261 its reverse (1624341218), we get a palindrome (9745775479).

The spelling of 8121434261 in words is "eight billion, one hundred twenty-one million, four hundred thirty-four thousand, two hundred sixty-one".