261144679 has 4 divisors (see below), whose sum is σ = 265570920. Its totient is φ = 256718440.

The previous prime is 261144673. The next prime is 261144749. The reversal of 261144679 is 976441162.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 261144679 - 2⁷ = 261144551 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261144673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2213032 + ... + 2213149.

It is an arithmetic number, because the mean of its divisors is an integer number (66392730).

Almost surely, 2^261144679 is an apocalyptic number.

261144679 is a deficient number, since it is larger than the sum of its proper divisors (4426241).

261144679 is an equidigital number, since it uses as much as digits as its factorization.

261144679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4426240.

The product of its digits is 72576, while the sum is 40.

The square root of 261144679 is about 16159.9715036877. The cubic root of 261144679 is about 639.1857148961.

The spelling of 261144679 in words is "two hundred sixty-one million, one hundred forty-four thousand, six hundred seventy-nine".