261766676869 has 2 divisors, whose sum is σ = 261766676870. Its totient is φ = 261766676868.

The previous prime is 261766676867. The next prime is 261766676933. The reversal of 261766676869 is 968676667162.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 148021020225 + 113745656644 = 384735^2 + 337262^2 .

It is a cyclic number.

It is not a de Polignac number, because 261766676869 - 2¹ = 261766676867 is a prime.

It is a super-2 number, since 2×261766676869² (a number of 24 digits) contains 22 as substring.

Together with 261766676867, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 261766676798 and 261766676807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261766676867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130883338434 + 130883338435.

It is an arithmetic number, because the mean of its divisors is an integer number (130883338435).

Almost surely, 2^261766676869 is an apocalyptic number.

It is an amenable number.

261766676869 is a deficient number, since it is larger than the sum of its proper divisors (1).

261766676869 is an equidigital number, since it uses as much as digits as its factorization.

261766676869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 329204736, while the sum is 70.

The spelling of 261766676869 in words is "two hundred sixty-one billion, seven hundred sixty-six million, six hundred seventy-six thousand, eight hundred sixty-nine".