1271531 has 2 divisors, whose sum is σ = 1271532. Its totient is φ = 1271530.

The previous prime is 1271521. The next prime is 1271551. The reversal of 1271531 is 1351721.

It is an a-pointer prime, because the next prime (1271551) can be obtained adding 1271531 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1271531 - 2¹⁴ = 1255147 is a prime.

It is a super-2 number, since 2×1271531² = 3233582167922, which contains 22 as substring.

It is a Chen prime.

It is equal to p₉₈₀₂₁ and since 1271531 and 98021 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (1271521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 635765 + 635766.

It is an arithmetic number, because the mean of its divisors is an integer number (635766).

2^1271531 is an apocalyptic number.

1271531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1271531 is an equidigital number, since it uses as much as digits as its factorization.

1271531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 210, while the sum is 20.

The square root of 1271531 is about 1127.6218337723. The cubic root of 1271531 is about 108.3367120577.

The spelling of 1271531 in words is "one million, two hundred seventy-one thousand, five hundred thirty-one".