261110778 has 8 divisors (see below), whose sum is σ = 522221568. Its totient is φ = 87036924.

The previous prime is 261110771. The next prime is 261110783. The reversal of 261110778 is 877011162.

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

261110778 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (261110771) 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 3 ways as a sum of consecutive naturals, for example, 21759226 + ... + 21759237.

It is an arithmetic number, because the mean of its divisors is an integer number (65277696).

Almost surely, 2^261110778 is an apocalyptic number.

261110778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261110778 is a wasteful number, since it uses less digits than its factorization.

261110778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43518468.

The product of its (nonzero) digits is 4704, while the sum is 33.

The square root of 261110778 is about 16158.9225507148. The cubic root of 261110778 is about 639.1580546571.

The spelling of 261110778 in words is "two hundred sixty-one million, one hundred ten thousand, seven hundred seventy-eight".