261789855 has 8 divisors (see below), whose sum is σ = 418863792. Its totient is φ = 139621248.

The previous prime is 261789833. The next prime is 261789877. The reversal of 261789855 is 558987162.

It is an interprime number because it is at equal distance from previous prime (261789833) and next prime (261789877).

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

It is not a de Polignac number, because 261789855 - 2⁶ = 261789791 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261789798 and 261789807.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 8726314 + ... + 8726343.

It is an arithmetic number, because the mean of its divisors is an integer number (52357974).

Almost surely, 2^261789855 is an apocalyptic number.

261789855 is a deficient number, since it is larger than the sum of its proper divisors (157073937).

261789855 is a wasteful number, since it uses less digits than its factorization.

261789855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17452665.

The product of its digits is 1209600, while the sum is 51.

The square root of 261789855 is about 16179.9213533317. The cubic root of 261789855 is about 639.7116661801.

The spelling of 261789855 in words is "two hundred sixty-one million, seven hundred eighty-nine thousand, eight hundred fifty-five".