815326769261 has 2 divisors, whose sum is σ = 815326769262. Its totient is φ = 815326769260.

The previous prime is 815326769239. The next prime is 815326769263. The reversal of 815326769261 is 162967623518.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 764654058025 + 50672711236 = 874445^2 + 225106^2 .

It is a cyclic number.

It is not a de Polignac number, because 815326769261 - 2¹⁸ = 815326507117 is a prime.

It is a super-2 number, since 2×815326769261² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 815326769263, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 815326769197 and 815326769206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (815326769263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407663384630 + 407663384631.

It is an arithmetic number, because the mean of its divisors is an integer number (407663384631).

Almost surely, 2^815326769261 is an apocalyptic number.

It is an amenable number.

815326769261 is a deficient number, since it is larger than the sum of its proper divisors (1).

815326769261 is an equidigital number, since it uses as much as digits as its factorization.

815326769261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6531840, while the sum is 56.

The spelling of 815326769261 in words is "eight hundred fifteen billion, three hundred twenty-six million, seven hundred sixty-nine thousand, two hundred sixty-one".