11881591 has 2 divisors, whose sum is σ = 11881592. Its totient is φ = 11881590.

The previous prime is 11881577. The next prime is 11881673. The reversal of 11881591 is 19518811.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11881591 - 2¹⁹ = 11357303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11881511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5940795 + 5940796.

It is an arithmetic number, because the mean of its divisors is an integer number (5940796).

Almost surely, 2^11881591 is an apocalyptic number.

11881591 is a deficient number, since it is larger than the sum of its proper divisors (1).

11881591 is an equidigital number, since it uses as much as digits as its factorization.

11881591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2880, while the sum is 34.

The square root of 11881591 is about 3446.9683781549. The cubic root of 11881591 is about 228.1873332135.

The spelling of 11881591 in words is "eleven million, eight hundred eighty-one thousand, five hundred ninety-one".