1268731281 has 4 divisors (see below), whose sum is σ = 1691641712. Its totient is φ = 845820852.

The previous prime is 1268731273. The next prime is 1268731283. The reversal of 1268731281 is 1821378621.

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 not a de Polignac number, because 1268731281 - 2³ = 1268731273 is a prime.

It is a super-2 number, since 2×1268731281² = 3219358126775801922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1268731283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 211455211 + ... + 211455216.

It is an arithmetic number, because the mean of its divisors is an integer number (422910428).

Almost surely, 2^1268731281 is an apocalyptic number.

It is an amenable number.

1268731281 is a deficient number, since it is larger than the sum of its proper divisors (422910431).

1268731281 is an equidigital number, since it uses as much as digits as its factorization.

1268731281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422910430.

The product of its digits is 32256, while the sum is 39.

The square root of 1268731281 is about 35619.2543577206. The cubic root of 1268731281 is about 1082.5713994085.

The spelling of 1268731281 in words is "one billion, two hundred sixty-eight million, seven hundred thirty-one thousand, two hundred eighty-one".