1271591 has 4 divisors (see below), whose sum is σ = 1275192. Its totient is φ = 1267992.

The previous prime is 1271561. The next prime is 1271597. The reversal of 1271591 is 1951721.

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

It is a cyclic number.

It is not a de Polignac number, because 1271591 - 2¹⁰ = 1270567 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 1271591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1271597) 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, 1205 + ... + 1998.

It is an arithmetic number, because the mean of its divisors is an integer number (318798).

2^1271591 is an apocalyptic number.

1271591 is a deficient number, since it is larger than the sum of its proper divisors (3601).

1271591 is an equidigital number, since it uses as much as digits as its factorization.

1271591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3600.

The product of its digits is 630, while the sum is 26.

The square root of 1271591 is about 1127.6484381224. The cubic root of 1271591 is about 108.3384160666.

The spelling of 1271591 in words is "one million, two hundred seventy-one thousand, five hundred ninety-one".