261868725829 has 2 divisors, whose sum is σ = 261868725830. Its totient is φ = 261868725828.

The previous prime is 261868725809. The next prime is 261868725851. The reversal of 261868725829 is 928527868162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132567353604 + 129301372225 = 364098^2 + 359585^2 .

It is a cyclic number.

It is not a de Polignac number, because 261868725829 - 2⁹ = 261868725317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261868725809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130934362914 + 130934362915.

It is an arithmetic number, because the mean of its divisors is an integer number (130934362915).

Almost surely, 2^261868725829 is an apocalyptic number.

It is an amenable number.

261868725829 is a deficient number, since it is larger than the sum of its proper divisors (1).

261868725829 is an equidigital number, since it uses as much as digits as its factorization.

261868725829 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46448640, while the sum is 64.

The spelling of 261868725829 in words is "two hundred sixty-one billion, eight hundred sixty-eight million, seven hundred twenty-five thousand, eight hundred twenty-nine".