261701685 has 40 divisors (see below), whose sum is σ = 536148096. Its totient is φ = 119633760.

The previous prime is 261701683. The next prime is 261701701. The reversal of 261701685 is 586107162.

It is not a de Polignac number, because 261701685 - 2¹ = 261701683 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261701681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 43321 + ... + 48990.

Almost surely, 2^261701685 is an apocalyptic number.

It is an amenable number.

261701685 is an abundant number, since it is smaller than the sum of its proper divisors (274446411).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261701685 is an equidigital number, since it uses as much as digits as its factorization.

261701685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92335 (or 92326 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 261701685 is about 16177.1964505597. The cubic root of 261701685 is about 639.6398404900.

The spelling of 261701685 in words is "two hundred sixty-one million, seven hundred one thousand, six hundred eighty-five".