1391866271 has 2 divisors, whose sum is σ = 1391866272. Its totient is φ = 1391866270.

The previous prime is 1391866247. The next prime is 1391866309. The reversal of 1391866271 is 1726681931.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1391866271 - 2¹⁰ = 1391865247 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1391866771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695933135 + 695933136.

It is an arithmetic number, because the mean of its divisors is an integer number (695933136).

Almost surely, 2^1391866271 is an apocalyptic number.

1391866271 is a deficient number, since it is larger than the sum of its proper divisors (1).

1391866271 is an equidigital number, since it uses as much as digits as its factorization.

1391866271 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 44.

The square root of 1391866271 is about 37307.7240125956. The cubic root of 1391866271 is about 1116.5182775222.

The spelling of 1391866271 in words is "one billion, three hundred ninety-one million, eight hundred sixty-six thousand, two hundred seventy-one".