261817967 has 8 divisors (see below), whose sum is σ = 279480960. Its totient is φ = 244543320.

The previous prime is 261817951. The next prime is 261817973. The reversal of 261817967 is 769718162.

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 261817967 - 2⁴ = 261817951 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 (261817667) 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, 95693 + ... + 98390.

It is an arithmetic number, because the mean of its divisors is an integer number (34935120).

Almost surely, 2^261817967 is an apocalyptic number.

261817967 is a deficient number, since it is larger than the sum of its proper divisors (17662993).

261817967 is a wasteful number, since it uses less digits than its factorization.

261817967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194173.

The product of its digits is 254016, while the sum is 47.

The square root of 261817967 is about 16180.7900610570. The cubic root of 261817967 is about 639.7345635923.

The spelling of 261817967 in words is "two hundred sixty-one million, eight hundred seventeen thousand, nine hundred sixty-seven".