261417605 has 8 divisors (see below), whose sum is σ = 316747392. Its totient is φ = 207103248.

The previous prime is 261417601. The next prime is 261417623. The reversal of 261417605 is 506714162.

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

It is a cyclic number.

It is not a de Polignac number, because 261417605 - 2² = 261417601 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261417601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 253289 + ... + 254318.

It is an arithmetic number, because the mean of its divisors is an integer number (39593424).

Almost surely, 2^261417605 is an apocalyptic number.

It is an amenable number.

261417605 is a deficient number, since it is larger than the sum of its proper divisors (55329787).

261417605 is a wasteful number, since it uses less digits than its factorization.

261417605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507715.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 261417605 is about 16168.4138059366. The cubic root of 261417605 is about 639.4083113802.

The spelling of 261417605 in words is "two hundred sixty-one million, four hundred seventeen thousand, six hundred five".