261218085 has 8 divisors (see below), whose sum is σ = 417948960. Its totient is φ = 139316304.

The previous prime is 261218081. The next prime is 261218117. The reversal of 261218085 is 580812162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 261218085 - 2² = 261218081 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261218081) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 8707255 + ... + 8707284.

It is an arithmetic number, because the mean of its divisors is an integer number (52243620).

Almost surely, 2^261218085 is an apocalyptic number.

It is an amenable number.

261218085 is a deficient number, since it is larger than the sum of its proper divisors (156730875).

261218085 is a wasteful number, since it uses less digits than its factorization.

261218085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17414547.

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 261218085 is about 16162.2425733560. The cubic root of 261218085 is about 639.2455995433.

The spelling of 261218085 in words is "two hundred sixty-one million, two hundred eighteen thousand, eighty-five".