268780781 has 4 divisors (see below), whose sum is σ = 269772864. Its totient is φ = 267788700.

The previous prime is 268780777. The next prime is 268780807. The reversal of 268780781 is 187087862.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 268780781 - 2² = 268780777 is a prime.

It is a super-2 number, since 2×268780781² = 144486216469939922, 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 (268780181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 495635 + ... + 496176.

It is an arithmetic number, because the mean of its divisors is an integer number (67443216).

Almost surely, 2^268780781 is an apocalyptic number.

It is an amenable number.

268780781 is a deficient number, since it is larger than the sum of its proper divisors (992083).

268780781 is an equidigital number, since it uses as much as digits as its factorization.

268780781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992082.

The product of its (nonzero) digits is 301056, while the sum is 47.

The square root of 268780781 is about 16394.5350955738. The cubic root of 268780781 is about 645.3560768502.

The spelling of 268780781 in words is "two hundred sixty-eight million, seven hundred eighty thousand, seven hundred eighty-one".