1272808809 has 40 divisors (see below), whose sum is σ = 1928836800. Its totient is φ = 836378784.

The previous prime is 1272808807. The next prime is 1272808813. The reversal of 1272808809 is 9088082721.

It is a happy number.

It is not a de Polignac number, because 1272808809 - 2¹ = 1272808807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1272808807) 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 39 ways as a sum of consecutive naturals, for example, 1966924 + ... + 1967570.

It is an arithmetic number, because the mean of its divisors is an integer number (48220920).

Almost surely, 2^1272808809 is an apocalyptic number.

It is an amenable number.

1272808809 is a deficient number, since it is larger than the sum of its proper divisors (656027991).

1272808809 is a wasteful number, since it uses less digits than its factorization.

1272808809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971 (or 962 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 1272808809 is about 35676.4461374728. The cubic root of 1272808809 is about 1083.7299044417.

The spelling of 1272808809 in words is "one billion, two hundred seventy-two million, eight hundred eight thousand, eight hundred nine".