261707879 has 4 divisors (see below), whose sum is σ = 268091040. Its totient is φ = 255324720.

The previous prime is 261707863. The next prime is 261707899. The reversal of 261707879 is 978707162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 978707162 = 2 ⋅489353581.

It is a cyclic number.

It is not a de Polignac number, because 261707879 - 2⁴ = 261707863 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 (261707899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3191519 + ... + 3191600.

It is an arithmetic number, because the mean of its divisors is an integer number (67022760).

Almost surely, 2^261707879 is an apocalyptic number.

261707879 is a deficient number, since it is larger than the sum of its proper divisors (6383161).

261707879 is an equidigital number, since it uses as much as digits as its factorization.

261707879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6383160.

The product of its (nonzero) digits is 296352, while the sum is 47.

The square root of 261707879 is about 16177.3878917457. The cubic root of 261707879 is about 639.6448868184.

The spelling of 261707879 in words is "two hundred sixty-one million, seven hundred seven thousand, eight hundred seventy-nine".