261019700009 has 2 divisors, whose sum is σ = 261019700010. Its totient is φ = 261019700008.

The previous prime is 261019700003. The next prime is 261019700063. The reversal of 261019700009 is 900007910162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 134141260009 + 126878440000 = 366253^2 + 356200^2 .

It is a cyclic number.

It is not a de Polignac number, because 261019700009 - 2²⁰ = 261018651433 is a prime.

It is not a weakly prime, because it can be changed into another prime (261019700003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130509850004 + 130509850005.

It is an arithmetic number, because the mean of its divisors is an integer number (130509850005).

Almost surely, 2^261019700009 is an apocalyptic number.

It is an amenable number.

261019700009 is a deficient number, since it is larger than the sum of its proper divisors (1).

261019700009 is an equidigital number, since it uses as much as digits as its factorization.

261019700009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6804, while the sum is 35.

The spelling of 261019700009 in words is "two hundred sixty-one billion, nineteen million, seven hundred thousand, nine".