1272317857 has 4 divisors (see below), whose sum is σ = 1276331796. Its totient is φ = 1268303920.

The previous prime is 1272317797. The next prime is 1272317861. The reversal of 1272317857 is 7587132721.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 526427136 + 745890721 = 22944^2 + 27311^2 .

It is a cyclic number.

It is not a de Polignac number, because 1272317857 - 2²⁷ = 1138100129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1272317867) 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, 2006494 + ... + 2007127.

It is an arithmetic number, because the mean of its divisors is an integer number (319082949).

Almost surely, 2^1272317857 is an apocalyptic number.

It is an amenable number.

1272317857 is a deficient number, since it is larger than the sum of its proper divisors (4013939).

1272317857 is an equidigital number, since it uses as much as digits as its factorization.

1272317857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4013938.

The product of its digits is 164640, while the sum is 43.

The square root of 1272317857 is about 35669.5648557702. The cubic root of 1272317857 is about 1083.5905465680.

The spelling of 1272317857 in words is "one billion, two hundred seventy-two million, three hundred seventeen thousand, eight hundred fifty-seven".