11541991 has 2 divisors, whose sum is σ = 11541992. Its totient is φ = 11541990.

The previous prime is 11541989. The next prime is 11542001. The reversal of 11541991 is 19914511.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11541991 - 2¹ = 11541989 is a prime.

Together with 11541989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11541941) 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, 5770995 + 5770996.

It is an arithmetic number, because the mean of its divisors is an integer number (5770996).

Almost surely, 2^11541991 is an apocalyptic number.

11541991 is a deficient number, since it is larger than the sum of its proper divisors (1).

11541991 is an equidigital number, since it uses as much as digits as its factorization.

11541991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1620, while the sum is 31.

The square root of 11541991 is about 3397.3505853827. The cubic root of 11541991 is about 225.9922661618.

The spelling of 11541991 in words is "eleven million, five hundred forty-one thousand, nine hundred ninety-one".