260812781 has 4 divisors (see below), whose sum is σ = 260851932. Its totient is φ = 260773632.

The previous prime is 260812777. The next prime is 260812807. The reversal of 260812781 is 187218062.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 187218062 = 2 ⋅93609031.

It can be written as a sum of positive squares in 2 ways, for example, as 252015625 + 8797156 = 15875^2 + 2966^2 .

It is a cyclic number.

It is not a de Polignac number, because 260812781 - 2² = 260812777 is a prime.

It is a super-2 number, since 2×260812781² = 136046613465907922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (260812711) 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, 6806 + ... + 23831.

It is an arithmetic number, because the mean of its divisors is an integer number (65212983).

Almost surely, 2^260812781 is an apocalyptic number.

It is an amenable number.

260812781 is a deficient number, since it is larger than the sum of its proper divisors (39151).

260812781 is an equidigital number, since it uses as much as digits as its factorization.

260812781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39150.

The product of its (nonzero) digits is 10752, while the sum is 35.

The square root of 260812781 is about 16149.6990993640. The cubic root of 260812781 is about 638.9148121935.

The spelling of 260812781 in words is "two hundred sixty million, eight hundred twelve thousand, seven hundred eighty-one".