1271136737809 has 3 divisors (see below), whose sum is σ = 1271137865257. Its totient is φ = 1271135610362.

The previous prime is 1271136737791. The next prime is 1271136737833. The reversal of 1271136737809 is 9087376311721.

The square root of 1271136737809 is 1127447.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1271136737809 - 2²³ = 1271128349201 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1271136737809.

It is not an unprimeable number, because it can be changed into a prime (1271136737209) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 563724 + ... + 1691170.

Almost surely, 2^{1271136737809} is an apocalyptic number.

1271136737809 is the 1127447-th square number.

1271136737809 is the 563724-th centered octagonal number.

It is an amenable number.

1271136737809 is a deficient number, since it is larger than the sum of its proper divisors (1127448).

1271136737809 is an frugal number, since it uses more digits than its factorization.

1271136737809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2254894 (or 1127447 counting only the distinct ones).

The product of its (nonzero) digits is 2667168, while the sum is 55.

The spelling of 1271136737809 in words is "one trillion, two hundred seventy-one billion, one hundred thirty-six million, seven hundred thirty-seven thousand, eight hundred nine".