1271972591 has 2 divisors, whose sum is σ = 1271972592. Its totient is φ = 1271972590.

The previous prime is 1271972539. The next prime is 1271972629. The reversal of 1271972591 is 1952791721.

It is a strong prime.

It is an emirp because it is prime and its reverse (1952791721) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1271972591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1271972291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 635986295 + 635986296.

It is an arithmetic number, because the mean of its divisors is an integer number (635986296).

Almost surely, 2^1271972591 is an apocalyptic number.

1271972591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1271972591 is an equidigital number, since it uses as much as digits as its factorization.

1271972591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 79380, while the sum is 44.

The square root of 1271972591 is about 35664.7247430847. The cubic root of 1271972591 is about 1083.4925205339.

The spelling of 1271972591 in words is "one billion, two hundred seventy-one million, nine hundred seventy-two thousand, five hundred ninety-one".