1272139928 has 16 divisors (see below), whose sum is σ = 2388449760. Its totient is φ = 635220000.

The previous prime is 1272139871. The next prime is 1272139969. The reversal of 1272139928 is 8299312721.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99863 + ... + 111878.

It is an arithmetic number, because the mean of its divisors is an integer number (149278110).

Almost surely, 2^1272139928 is an apocalyptic number.

It is an amenable number.

1272139928 is a deficient number, since it is larger than the sum of its proper divisors (1116309832).

1272139928 is a wasteful number, since it uses less digits than its factorization.

1272139928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212498 (or 212494 counting only the distinct ones).

The product of its digits is 108864, while the sum is 44.

The square root of 1272139928 is about 35667.0706394568. The cubic root of 1272139928 is about 1083.5400321546.

The spelling of 1272139928 in words is "one billion, two hundred seventy-two million, one hundred thirty-nine thousand, nine hundred twenty-eight".