261332785 has 16 divisors (see below), whose sum is σ = 373982976. Its totient is φ = 171407808.

The previous prime is 261332779. The next prime is 261332791. The reversal of 261332785 is 587233162.

It is an interprime number because it is at equal distance from previous prime (261332779) and next prime (261332791).

It is a cyclic number.

It is not a de Polignac number, because 261332785 - 2⁹ = 261332273 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 161514 + ... + 163123.

It is an arithmetic number, because the mean of its divisors is an integer number (23373936).

Almost surely, 2^261332785 is an apocalyptic number.

It is an amenable number.

261332785 is a deficient number, since it is larger than the sum of its proper divisors (112650191).

261332785 is a wasteful number, since it uses less digits than its factorization.

261332785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324672.

The product of its digits is 60480, while the sum is 37.

The square root of 261332785 is about 16165.7905776365. The cubic root of 261332785 is about 639.3391493973.

The spelling of 261332785 in words is "two hundred sixty-one million, three hundred thirty-two thousand, seven hundred eighty-five".