1261698017 has 2 divisors, whose sum is σ = 1261698018. Its totient is φ = 1261698016.

The previous prime is 1261698013. The next prime is 1261698049. The reversal of 1261698017 is 7108961621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 797554081 + 464143936 = 28241^2 + 21544^2 .

It is a cyclic number.

It is not a de Polignac number, because 1261698017 - 2² = 1261698013 is a prime.

It is a super-2 number, since 2×1261698017² = 3183763772203464578, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1261698013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630849008 + 630849009.

It is an arithmetic number, because the mean of its divisors is an integer number (630849009).

Almost surely, 2^1261698017 is an apocalyptic number.

It is an amenable number.

1261698017 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261698017 is an equidigital number, since it uses as much as digits as its factorization.

1261698017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 41.

The square root of 1261698017 is about 35520.3887506880. The cubic root of 1261698017 is about 1080.5672651517.

The spelling of 1261698017 in words is "one billion, two hundred sixty-one million, six hundred ninety-eight thousand, seventeen".