11681491 has 2 divisors, whose sum is σ = 11681492. Its totient is φ = 11681490.

The previous prime is 11681489. The next prime is 11681543. The reversal of 11681491 is 19418611.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11681491 - 2¹ = 11681489 is a prime.

Together with 11681489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11681191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5840745 + 5840746.

It is an arithmetic number, because the mean of its divisors is an integer number (5840746).

Almost surely, 2^11681491 is an apocalyptic number.

11681491 is a deficient number, since it is larger than the sum of its proper divisors (1).

11681491 is an equidigital number, since it uses as much as digits as its factorization.

11681491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 31.

The square root of 11681491 is about 3417.8196266041. The cubic root of 11681491 is about 226.8990928533.

The spelling of 11681491 in words is "eleven million, six hundred eighty-one thousand, four hundred ninety-one".