1271989133 has 4 divisors (see below), whose sum is σ = 1283245788. Its totient is φ = 1260732480.

The previous prime is 1271989129. The next prime is 1271989163. The reversal of 1271989133 is 3319891721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3319891721 = 2377 ⋅1396673.

It can be written as a sum of positive squares in 2 ways, for example, as 688380169 + 583608964 = 26237^2 + 24158^2 .

It is a cyclic number.

It is not a de Polignac number, because 1271989133 - 2² = 1271989129 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1271989123) 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, 5628158 + ... + 5628383.

It is an arithmetic number, because the mean of its divisors is an integer number (320811447).

Almost surely, 2^1271989133 is an apocalyptic number.

It is an amenable number.

1271989133 is a deficient number, since it is larger than the sum of its proper divisors (11256655).

1271989133 is a wasteful number, since it uses less digits than its factorization.

1271989133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11256654.

The product of its digits is 81648, while the sum is 44.

The square root of 1271989133 is about 35664.9566521537. The cubic root of 1271989133 is about 1083.4972174526.

The spelling of 1271989133 in words is "one billion, two hundred seventy-one million, nine hundred eighty-nine thousand, one hundred thirty-three".