781268 has 12 divisors (see below), whose sum is σ = 1376340. Its totient is φ = 388032.

The previous prime is 781247. The next prime is 781271. The reversal of 781268 is 862187.

It can be written as a sum of positive squares in 2 ways, for example, as 386884 + 394384 = 622^2 + 628^2 .

It is a super-2 number, since 2×781268² = 1220759375648, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

781268 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 128 + ... + 1256.

It is an arithmetic number, because the mean of its divisors is an integer number (114695).

2⁷⁸¹²⁶⁸ is an apocalyptic number.

It is an amenable number.

781268 is a deficient number, since it is larger than the sum of its proper divisors (595072).

781268 is a wasteful number, since it uses less digits than its factorization.

781268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1306 (or 1304 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 781268 is about 883.8936587622. The cubic root of 781268 is about 92.1014947946.

The spelling of 781268 in words is "seven hundred eighty-one thousand, two hundred sixty-eight".