261883985 has 8 divisors (see below), whose sum is σ = 342830016. Its totient is φ = 190461040.

The previous prime is 261883967. The next prime is 261883987. The reversal of 261883985 is 589388162.

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

It is not a de Polignac number, because 261883985 - 2¹⁴ = 261867601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261883987) 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, 2380709 + ... + 2380818.

It is an arithmetic number, because the mean of its divisors is an integer number (42853752).

Almost surely, 2^261883985 is an apocalyptic number.

It is an amenable number.

261883985 is a deficient number, since it is larger than the sum of its proper divisors (80946031).

261883985 is a wasteful number, since it uses less digits than its factorization.

261883985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4761543.

The product of its digits is 829440, while the sum is 50.

The square root of 261883985 is about 16182.8299441105. The cubic root of 261883985 is about 639.7883292520.

The spelling of 261883985 in words is "two hundred sixty-one million, eight hundred eighty-three thousand, nine hundred eighty-five".